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EG4 FlexBOSS21 & EG4 WallMount Battery Bundle

EG4 FlexBOSS21 & EG4 WallMount Battery Bundle
Save 10% Save 12%
$8,047.98
$8,047.98 - $32,481.83
$8,047.98
$7,101.88
$7,101.88 - $29,081.63
$7,101.88
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Inverter Option: 1 EG4 FlexBOSS21 + 1 x EG4-314Ah Indoor WallMount Battery
EG4 FlexBoss21 Manual & Spec Sheet

View Manual HERE
View Spec Sheet HERE

WallMount Indoor Lithium Battery Guides

View Quick Start Guide HERE
View Spec Sheet HERE

View Connection Overview & Paralleling Guide HERE

View Device Monitoring & Settings Guide HERE

EG4

EG4 FlexBOSS21 & EG4 WallMount Battery Bundle

The EG4 FlexBOSS21 + WallMount Indoor Battery Bundle delivers a powerful, all-in-one solution for whole-home energy independence, backup, and savings. Designed to seamlessly integrate solar, battery, and grid power, this system gives you reliable control over your energy—keeping your home running smoothly during outages while maximizing everyday efficiency.

Ideal for homeowners and small businesses looking for a dependable, scalable energy solution. Perfect for whole-home backup, off-grid living, or reducing reliance on the grid through solar self-consumption and time-of-use savings—all while maintaining seamless, uninterrupted power.

EG4 FlexBOSS21 & EG4 WallMount Battery Bundle
Lowest Price Guarantee
Authorized EG4 Dealer
Genuine EG4 Equipment
10-Year Warranty Coverage
Free Shipping
0% APR Financing via Affirm

Why the EG4 FlexBOSS21 & EG4 WallMount Battery Bundle

Whole-Home Backup Confidence

Keep essential systems—and even large loads like a 5-ton AC—running without interruption during outages.

High Solar Input for Maximum Production

Supports up to 21kW of PV input with three MPPTs, helping you capture more energy throughout the day.

Flexible Energy Control

Operate off-grid, use grid support, or sell excess energy back—giving you full control over how you power your home.

Smart Monitoring & Remote Access

Manage your system from anywhere with EG4 monitoring software, including real-time data and mobile alerts.

Safe, Certified, and Built to Last

Advanced protections including rapid shutdown, arc fault detection, and a robust BMS for long-term reliability.

Output

Split-phase 120/240V

EG4 FlexBOSS21 & EG4 WallMount Battery Bundle Specifications

PV Input Up to 21kW
Max PV Voltage 600V DC
Output Split-phase 120/240V
Certifications UL 1741, CEC Listed
Nominal Voltage 51.2V
Capacity 314Ah
Energy 16 kWh
Max Continuous Output 200A
Peak Output 12.8 kW
Your Satisfaction with EG4 is Guaranteed 10-Year Limited Warranty

Documentation & Downloads

EG4 FlexBOSS21 & EG4 WallMount Battery Bundle Spec Sheet (PDF)

Lowest Price Guarantee

Find it cheaper at another authorized EG4 dealer? Call us before you order and we will take care of you.

Authorized EG4 Dealer

This is genuine EG4 equipment, sold and supported by Renewable Outdoors as an authorized dealer. Coverage: 10-Year per the manufacturer terms stated for this product.

Help From People Who Sell These Every Day

Call (303) 876-7654. We would rather spend ten minutes sizing your system correctly than process a return later.

EG4 FlexBOSS21 & EG4 WallMount Battery Bundle: Frequently Asked Questions

How much energy does the FlexBOSS21 & EG4 WallMount Battery Bundle provide?
The FlexBOSS21 & EG4 WallMount Battery Bundle is rated at 314Ah (Capacity). That figure comes straight from the manufacturer's specifications for this model, and the full spec sheet is linked above under Documentation & Downloads.
What certifications does the FlexBOSS21 & EG4 WallMount Battery Bundle carry?
The FlexBOSS21 & EG4 WallMount Battery Bundle carries these certifications: UL 1741, CEC Listed.
What's covered under the warranty?
EG4 backs the FlexBOSS21 & EG4 WallMount Battery Bundle with a 10-Year warranty per the manufacturer's terms stated for this product. As your retailer, Renewable Outdoors can also help you navigate a warranty claim — call us at (303) 876-7654.
What voltage does the FlexBOSS21 & EG4 WallMount Battery Bundle run on?
The FlexBOSS21 & EG4 WallMount Battery Bundle operates at 600V DC (Max PV Voltage). Make sure the rest of your system is built for the same voltage before ordering.
How does solar charging work with the FlexBOSS21 & EG4 WallMount Battery Bundle?
High Solar Input for Maximum Production: Supports up to 21kW of PV input with three MPPTs, helping you capture more energy throughout the day.
Is this genuine EG4 equipment?
Yes. Renewable Outdoors is an authorized EG4 dealer, and this product is genuine EG4 equipment.
Does Renewable Outdoors offer financing or price matching?
Yes. We offer 0% APR financing options through Affirm at checkout, and the FlexBOSS21 & EG4 WallMount Battery Bundle is backed by our Lowest Price Guarantee — if you find it cheaper at another authorized EG4 dealer, call us at (303) 876-7654 before you order and we will take care of you.
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