EG4 FlexBOSS 16kw AC Hybrid Inverter | 48V Split Phase | 21kW PV Input | [V1.1] Newest Version - ShopSolar.com

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SKU 1511049

by EG4

EG4 FlexBOSS 16kw AC Hybrid Inverter | 48V Split Phase | 21kW PV Input | [V1.1] Newest Version

Name: EG4 FlexBOSS 16kw AC Hybrid Inverter | 48V Split Phase | 21kW PV Input | [V1.1] Newest Version
Brand: EG4
Price: 4199.0 USD
Availability: InStock

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EG4 FlexBOSS 16kw AC Hybrid Inverter | 48V Split Phase | 21kW PV Input | [V1.1] Newest Version

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In Stock Get yours today!

10+ sold In the last 7 days

Free Returns Free Returns within 30 Days of Purchase

Lifetime Customer Support Unlimited lifetime support, always available.

General Overview

Products Details

Reviews

FAQ's

Why Choose Shop Solar

Powerful, Flexible, and Built for Energy Independence

The EG4 FlexBOSS21 (V1.1) is a versatile 48V split-phase hybrid inverter/charger, delivering powerful performance and seamless energy management. Designed to handle heavy loads—including a 5-ton AC unit—this advanced inverter supports 21kW of PV input and can be paralleled up to 16 units, offering a staggering 256kW total continuous output.

Equipped with three MPPTs for maximum solar efficiency, the FlexBOSS21 is fully compatible with the latest EG4 monitoring software, allowing for remote management, mobile notifications, and real-time adjustments. Seamlessly integrates with EG4 GridBOSS for complete control over your Energy Storage System (ESS).

Key Features & Benefits

✅ Flexible Power Management – Operate off-grid, with grid support, or sell excess power back to the grid.
✅ High PV Input Voltage (600V DC) – Reduces cabling costs and increases system efficiency.
✅ Scalable & Powerful – Parallel up to 16 units for large-scale energy solutions.
✅ Smart Connectivity – Remote access via Wi-Fi and closed-loop communication with compatible batteries.
✅ Advanced Safety Features – Includes rapid shutdown, ground fault monitoring, arc-fault protection, and compliance with top industry standards.

🔹 Certified for Safety & Compliance:

UL 1741 Certified
CEC Solar Equipment Listed

Technical Specifications

📏 Input Voltage Range: 120/240VAC (Split-phase) | 120/208VAC
⚡ Output Power: 16kW continuous (PV input), with 24kW peak surge capacity
📐 Dimensions: 29.5” x 20.5” x 11.2”
⚖️ Weight: 88 lbs
📜 Warranty: 10-year standard warranty covering all major components

Why Choose the EG4 FlexBOSS21?

The FlexBOSS21 offers next-level efficiency, durability, and innovation, making it an ideal solution for both residential and commercial applications. With advanced remote monitoring, seamless grid integration, and high-output capabilities, this inverter ensures reliable power and complete energy control.

💡 Upgrade Your Solar System Today!
Take control of your energy with the EG4 FlexBOSS21 Hybrid Inverter and maximize your solar potential.

🔋 Experience the power of the EG4 FlexBOSS21—built for performance, reliability, and total energy independence.

What's Included:

1 x EG4 FlexBOSS21 Hybrid Inverter
1 x Wi-Fi Dongle
1 x Wall Mount TEmplate
2 x 1" CT
2 x L Bracket
4 x RJ45 Terminals
1 x Mounting Bracket
4 x Phillips Head Screw M5x10
4 x Phillips Head Screw M3x10
1 x Battery Communication Cable L=2m (Orange)
1 x Parallel Communication Cable L=2m (Grey)
6 x Self-Tapping Screws
6 x Expansion Bolts
User Manuals & Any Related Certifications
Fast, Reliable Shipping
Lifetime Customer Support

Product Specifications:

Specifications
Compatible Battery Types	Lead-acid/ Lithium
Max. Charge/Discharge Power	12000W
Nominal Voltage	48VDC
Voltage Range	40 – 60 VDC
Recommended Battery Capacity Per Inverter	>300Ah
Max Units in Parallel	16
Product Dimensions (HxWxD)	30.43 × 22.28 × 11.22 in. (750 × 520 × 285 mm)
Unit Weight	88 lbs. (52 kg)
Design Topology	High Frequency – Transformerless
Relative Humidity	0 – 100%
Operating Altitude	<6561 ft (<2000 m)
Operating Ambient Temperature Range	-13° – 140°F (-25° – 60°C)
Storage Ambient Temperature Range	-13° – 140°F (-25° – 60°C)
Noise Emission (Typical)	<50dB @ 3 ft
Communication Interface	RS485/Wi-Fi/CAN
Standard Warranty	10-year standard warranty*
Outdoor Rating	NEMA 4X

What is your return policy?

Returns are free in the first 30 days with no restocking or processing fees, although the customer may be responsible for paying return shipping. See our complete return policy on our Shipping, Delivery, and Returns page linked in the footer of this website.

What’s covered by your return policy?

Our returns policy covers all purchases made through Shop Solar. For warranty issues, as authorized distributors, we honor the full manufacturer warranty of ALL the brands on our website. See our complete returns and warranty policies on our Shipping, Deliver, and Returns page.

How long will it take to receive my order?

All orders are processed within 72 hours and you can expect delivery on most orders within 5-7 business days. You will receive access to our customer portal after ordering, where it is easy to track all your shipments. See our Shipping, Delivery and Returns page for more details.

What are your financing and payment options?

We offer several ways to pay to make getting your solar kit simple:

Credit Card: if the purchase is greater than your card’s limit, you can split the cost onto multiple cards as well as Paypal, financing through Affirm, and ACH/bank transfer
You can arrange financing during the checkout process, or scroll further down this page for more details. Please note, if you'd like to finance your order, you can do so instantly, right at checkout.

How does your Lifetime Customer Support work?

Our legendary lifetime customer support has helped make us the #1 online solar retailer! We have a dedicated team of solar professionals standing by to help you navigate the world of solar with ease. From selecting the perfect solar kit to installation and beyond, we provide support and expertise at every step of the journey.If you need help with ordering, shipping, troubleshooting, expanding your system, warranty issues, or anything else you have questions about for as long as you own your Shop Solar Kits equipment, we’ve got you covered: we’re always only a phone call or email away.

Top Solar Company in the USA

The prestigious ranking by Consumer Affairs is based on comprehensive evaluations, including ratings and reviews, equipment options, support services, pricing transparency, warranties, and various other factors. Among the top 6 nominated companies, Shop Solar stands out with the highest review rating, reaffirming its dedication to customer satisfaction and product quality.

Best Components, Lowest Prices

We cut out the bloat of traditional solar companies and pass those savings off to you. Plus, we provide free shipping on all solar kits and lifetime customer service on everything we sell.

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Our team of solar professionals is here to help you navigate the world of solar with ease. From selecting the perfect solar kit to installation and beyond, we provide support and expertise at every step of the journey.

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We’re people just like you

We’re not corporate and neither are our customers. We’re just a group of 50+ solar enthusiasts who are passionate about providing an honest, no-BS way for anyone, anywhere to improve their lives and the world around them with solar power.

Trusted Solar Authority

With over 40,000+ happy customers, 2,500+ positive reviews, and decades of experience in the industry, we’re proud to say we’re America’s #1 solar power solutions provider. You can trust us to provide you with top-notch products and legendary customer service at every step of the way.

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Why pay more when you can go solar your way? With our DIY+ model, you become the master of your own solar project - we call it being your own general contractor, using our seasoned technicians to help guide you at every turn. So you can skip the high-commission salespeople and source your own top-tier equipment from us, and if you need a professional installer, we can help with that too. It’s solar, but smarter and more rewarding—because who said going green couldn’t also save you some green?

Solar Power, Your Way - Expert Guidance Included

Become Your Own Solar Contractor with Our DIY+ Program

Save Thousands with Our DIY Solar Kits and Support

Go Green and Save Green with Our Do-It-Yourself Solar Solution

Solar Power, Your Way - Expert Guidance Included

Become Your Own Solar Contractor with Our DIY+ Program

Save Thousands with Our DIY Solar Kits and Support

Go Green and Save Green with Our Do-It-Yourself Solar Solution

Why Choose Shop Solar

What To Expect - Complete Kits

We've been providing America and Canada with complete solar kits since 2018. Our mission is to make solar simple, which is why our complete packages contain every part and piece that you'd ever need. Designed by our expert solar and electrical engineers, we can have the entire kit shipped to your door. All of our kits come with diagrams and videos along with a lifetime of customer support.

Top Solar Company in the USA

The prestigious ranking by Consumer Affairs is based on comprehensive evaluations, including ratings and reviews, equipment options, support services, pricing transparency, warranties, and various other factors. Among the top 6 nominated companies, Shop Solar stands out with the highest review rating, reaffirming its dedication to customer satisfaction and product quality.

Best Components, Lowest Prices

We cut out the bloat of traditional solar companies and pass those savings off to you. Plus, lifetime customer service on everything we sell.

Expert Guidance

Our team of solar professionals is here to help you navigate the world of solar with ease. From selecting the perfect solar kit to installation and beyond, we provide support and expertise at every step of the journey.

We’re people just like you

We’re not corporate and neither are our customers. We’re just a group of 50+ solar enthusiasts who are passionate about providing an honest, no-BS way for anyone, anywhere to improve their lives and the world around them with solar power.

Trusted Solar Authority

With over 40,000+ happy customers, 2,500+ positive reviews, and decades of experience in the industry, we’re proud to say we’re America’s #1 solar power solutions provider. You can trust us to provide you with top-notch products and legendary customer service at every step of the way.

What to Expect - Solar Panels

Get to know the top-tier solar panels included in your kit. These panels are designed to deliver consistent & reliable performance, ensuring your system powers your needs with ease.

What to Expect - Batteries

Learn about the high-quality batteries included in every solar kit, designed to provide reliable energy storage for all your needs. These batteries ensure your system delivers consistent power when you need it most.

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No Money Down Today

Some payment plans offer as little as no money down, if you qualify.*` - Survey at checkout!

How we compare to the others!

Tired of the costly and complicated traditional solar sales model? At ShopSolar.com, we streamline the process with our digital-first platform, offering one-click complete solar power solutions that save you up to 50%, often including batteries, for true energy independence. Join over 45,000 satisfied customers enjoying affordable solar energy. Start your journey towards saving thousands at ShopSolar.com today!

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Customer Success Stories

TP

Troy P

EG4 off-grid base kit, Happy with my purchase.

This is the first stage of my three planned purches. I got the eg4 inverter 6000 XP base kit with six 400 watt panels and the two server rack batteries. Did a little online research and followed the instructions and it got set up without any issues. Right now I'm just running it in my garage on a single outlet and have been running dual 750 watt water distillers with it. Once I get the second inverter and a bunch more panels and batteries, I plan on attaching it to my subpanel in my house that has my lights and outlets and appliances on it. Then I'll get a soft start for my AC and blower and run it on my main panel.

JB

Jacob B

Easy Process, Genuine Support

Trying to pick the correct solar system for your needs can be very technical and frustrating. I wanted to thank Yvhan and the Shop Solar team for their patience and helpful attitudes through multiple calls. I feel like we were able to narrow it down to what worked for me and my family. My system works great and I couldn't be happier to have picked Shop Solar.

PB

Patrick B

Off Grid Solar Purchase

I wanted to get an offgrid solar system for years but didn’t know where to start. I found Shop Solar on Facebook and decided to submit a quote. Within 24 hours I had a custom proposal that was almost half the price of the companies I had previously got quotes from. My wife and I decided to order online and the kit came in a timely manner and it was an easy install. Great company to work with!

JM

James Martin

Highly Recommend

I would like to take the time to express the outstanding service that I was provided with by Shop Solar. They provided me with all the answers to my questions, and after reviewing our quote over the phone I felt comfortable proceeding to order my kit. It’s exactly what I needed and they were there to help us over the phone when we had questions installing it. I highly recommend others in need to choose Shop Solar Kits.

BH

Brian H

Solar Kit for Mobile Work Van

As a professional videographer, I needed reliable power on the go. ShopSolar's Delta Pro and roof-mounted panels were the perfect solution. Setup was easy, and the kit included everything needed. The Delta Pro powers my cameras, lights, laptop, and a small fridge with impressive battery capacity.

KS

Keith S

Best Tech Support

You folks have been wonderful guiding me through the ins and outs of going solar. Plus your tech guys Rod and Nelson are the absolute best. They explained all the different aspects of inverters, batteries and how to keep them in top condition. Too much more to put here… but no other company has the 100% tech support you provide for your customers!

CA

Coll A

Great Experience

My experience with Shop Solar has been excellent. Before the sales, they answered all my questions to assure that I got what I needed. After the sales they continued to support me with answers and help. I had a warranty issue with a unit, and it was handled as well as possible. I would recommend them to anyone looking to go solar.

TP

Troy P

EG4 off-grid base kit, Happy with my purchase.

This is the first stage of my three planned purches. I got the eg4 inverter 6000 XP base kit with six 400 watt panels and the two server rack batteries. Did a little online research and followed the instructions and it got set up without any issues. Right now I'm just running it in my garage on a single outlet and have been running dual 750 watt water distillers with it. Once I get the second inverter and a bunch more panels and batteries, I plan on attaching it to my subpanel in my house that has my lights and outlets and appliances on it. Then I'll get a soft start for my AC and blower and run it on my main panel.

JB

Jacob B

Easy Process, Genuine Support

Trying to pick the correct solar system for your needs can be very technical and frustrating. I wanted to thank Yvhan and the Shop Solar team for their patience and helpful attitudes through multiple calls. I feel like we were able to narrow it down to what worked for me and my family. My system works great and I couldn't be happier to have picked Shop Solar.

PB

Patrick B

Off Grid Solar Purchase

I wanted to get an offgrid solar system for years but didn’t know where to start. I found Shop Solar on Facebook and decided to submit a quote. Within 24 hours I had a custom proposal that was almost half the price of the companies I had previously got quotes from. My wife and I decided to order online and the kit came in a timely manner and it was an easy install. Great company to work with!

JM

James Martin

Highly Recommend

I would like to take the time to express the outstanding service that I was provided with by Shop Solar. They provided me with all the answers to my questions, and after reviewing our quote over the phone I felt comfortable proceeding to order my kit. It’s exactly what I needed and they were there to help us over the phone when we had questions installing it. I highly recommend others in need to choose Shop Solar Kits.

BH

Brian H

Solar Kit for Mobile Work Van

As a professional videographer, I needed reliable power on the go. ShopSolar's Delta Pro and roof-mounted panels were the perfect solution. Setup was easy, and the kit included everything needed. The Delta Pro powers my cameras, lights, laptop, and a small fridge with impressive battery capacity.

KS

Keith S

Best Tech Support

You folks have been wonderful guiding me through the ins and outs of going solar. Plus your tech guys Rod and Nelson are the absolute best. They explained all the different aspects of inverters, batteries and how to keep them in top condition. Too much more to put here… but no other company has the 100% tech support you provide for your customers!

CA

Coll A

Great Experience

My experience with Shop Solar has been excellent. Before the sales, they answered all my questions to assure that I got what I needed. After the sales they continued to support me with answers and help. I had a warranty issue with a unit, and it was handled as well as possible. I would recommend them to anyone looking to go solar.

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Shop Securely, Trusted Supplier, 100% Satisfaction

Trusted Company, Real Products, Lifetime Support

Avoid Scams, Buy with Confidence, Enjoy Peace of Mind

Manufacturer Warranty, Exceptional Service

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EG4 FlexBOSS 16kw AC Hybrid Inverter | 48V Split Phase | 21kW PV Input | [V1.1] Newest Version

Powerful, Flexible, and Built for Energy Independence

Key Features & Benefits

Technical Specifications

Why Choose the EG4 FlexBOSS21?

What's Included:

Product Specifications:

What is your return policy?

What’s covered by your return policy?

How long will it take to receive my order?

What are your financing and payment options?

How does your Lifetime Customer Support work?

Top Solar Company in the USA

Best Components, Lowest Prices

Expert Guidance

We’re people just like you

Trusted Solar Authority

Prepare for Anything

Solar Power Made Easy

Secure Your Independence

Solar That Makes Sense - DIY+

Solar Power, Your Way - Expert Guidance Included

Become Your Own Solar Contractor with Our DIY+ Program

Save Thousands with Our DIY Solar Kits and Support

Go Green and Save Green with Our Do-It-Yourself Solar Solution

Solar Power, Your Way - Expert Guidance Included

Become Your Own Solar Contractor with Our DIY+ Program

Save Thousands with Our DIY Solar Kits and Support

Go Green and Save Green with Our Do-It-Yourself Solar Solution

Why Choose Shop Solar

What To Expect - Complete Kits

Top Solar Company in the USA

Best Components, Lowest Prices

Expert Guidance

We’re people just like you

Trusted Solar Authority

What to Expect - Solar Panels

What to Expect - Batteries

Go Solar Now, Pay Later

Quick and Easy Application

Poor Credit or No Credit?

No Money Down Today

How we compare to the others!

Customer Success Stories

EG4 off-grid base kit, Happy with my purchase.

Easy Process, Genuine Support

Off Grid Solar Purchase

Highly Recommend

Solar Kit for Mobile Work Van

Best Tech Support

Great Experience

EG4 off-grid base kit, Happy with my purchase.

Easy Process, Genuine Support

Off Grid Solar Purchase

Highly Recommend

Solar Kit for Mobile Work Van

Best Tech Support

Great Experience

Shop Securely, Trusted Supplier, 100% Satisfaction

Trusted Company, Real Products, Lifetime Support

Avoid Scams, Buy with Confidence, Enjoy Peace of Mind

Manufacturer Warranty, Exceptional Service

Shop Securely, Trusted Supplier, 100% Satisfaction

Trusted Company, Real Products, Lifetime Support

Avoid Scams, Buy with Confidence, Enjoy Peace of Mind

Manufacturer Warranty, Exceptional Service

Be Smart, Buy From an Authorized Dealer

SOLAR + STORAGE MINI COURSE

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