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Ships by freight. This item is too large for parcel delivery. After you order, we'll contact you within 1 business day with the freight cost and delivery options (liftgate, residential). Your order ships only after you approve the quote.
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- 57.2kWh LFP storage, 16kW rated AC output
- Up to 21kW of solar input
- GridBOSS 200A whole-home MID with smart loads
- 1x FlexBOSS21 hybrid inverter
- Outdoor-rated: NEMA 4X inverters, All Weather batteries
- Includes conduit boxes, cables, screen kit, breakers
- 10-year warranty on inverter, GridBOSS and batteries
Ships by LTL freight. Too large for parcel delivery. Questions on freight? Call (888) 831-0450.
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Product Documents
- EG4 GridBOSS MID Spec Sheet (v1.1.8)
- EG4 FlexBOSS21 Hybrid Inverter Spec Sheet (v1.3.0)
- EG4 WallMount All Weather 280Ah (14.3kWh) Battery Spec Sheet (v1.2.1)
- EG4 GridBOSS User Manual (MI-200-2P-HYB-AW-03, v2.0.7)
- EG4 FlexBOSS21 Hybrid Inverter User Manual (v1.3.7)
- EG4 WallMount 280Ah All Weather Battery User Manual (v1.6.3)
- EG4 GridBOSS Warranty Document
- EG4 FlexBOSS21 Warranty Document
One FlexBOSS21 and four 280Ah WallMount batteries (57.2kWh), coordinated by a GridBOSS MID. It's a long-runtime system for homes that care more about how long the power lasts than about peak output.
Highlights
- 57.2kWh of storage for multi-day outage coverage
- Up to 12kW continuous battery-only output
- GridBOSS load management
- Solar-ready with up to 21kW of PV
What's included
- 1× EG4 FlexBOSS21 hybrid inverter
- 4× EG4 280Ah WallMount battery (14.3kWh each)
- 1× EG4 GridBOSS MID
System at a glance
| AC output | Up to 16kW (with PV + grid); up to 12kW continuous from batteries |
| Battery storage | 57.2kWh LiFePO4 |
| Max PV input | 21kW |
| Energy management | GridBOSS MID, 200A service entrance |
Warranty & shipping
- EG4 warranties: FlexBOSS21 10 years, WallMount batteries 10 years, GridBOSS 10 years
- Combined weight of major components: ~1,415 lbs. Ships in multiple pieces by freight
Actual backup runtime depends on your home's loads and configuration. Solar panels, racking, breakers and wiring are not included. Professional installation by a licensed electrician is recommended.
| Manufacturer | EG4 Electronics (bundle) |
|---|---|
| Bundle SKU | BNDL-E1657 |
| Battery Storage | 57.2kWh |
| Rated Power | 16kW |
| Max PV Input | 21kW |
| Battery-Only Continuous Output | up to 12kW |
| Includes | 1x EG4 GridBOSS MID v3.1 (Microgrid Interconnect Device (MID); 200A service entrance (350A bus, software limited to 200A); 3 x 90A (12kPV, 18kPV, FlexBOSS18, FlexBOSS21)) |
| Includes | 1x EG4 FlexBOSS21 Hybrid Inverter (16kW (66.7A); 12kW (50A); 21kW (STC)) |
| Includes | 4x EG4 WallMount All Weather Battery 48V 280Ah 14.3kWh (LiFePO4; 51.2V; 280Ah) |
| Includes | 4x EG4 280Ah/314Ah All Weather Conduit Box |
| Includes | 3x EG4 280Ah/314Ah WallMount Battery Paralleling Cable Kit |
| Includes | 1x EG4 FlexBOSS LCD Screen Kit |
| Includes | 1x BSB 90A AC Circuit Breaker |
| Includes | 1x Eaton CSR 200A Main Breaker |
Specifications are from the manufacturer and may change. Questions? Call (888) 831-0450.
EG4 Limited Warranty (per component): GridBOSS 10-year limited; FlexBOSS21 10-year limited; WallMount AW 280Ah 10-year limited, prorated
| GridBOSS | 10-year limited |
|---|---|
| FlexBOSS21 | 10-year limited |
| WallMount AW 280Ah | 10-year limited, prorated |
| How to claim | contact original place of purchase (Sky Solar USA) / EG4 |
Download: EG4 GridBOSS Warranty Document
Download: EG4 FlexBOSS21 Warranty Document
Manufacturer warranties are provided by the manufacturer. Keep your invoice as proof of purchase. Questions about a warranty claim? Call (888) 831-0450.