EG4 Electronics FlexBOSS21 Hybrid Inverter
Verified comparison specs
Verified from EG4 Electronics's spec sheet, Sep 30, 2026.
Questions people ask about the EG4 Electronics FlexBOSS21 Hybrid Inverter
How much does the EG4 Electronics FlexBOSS21 Hybrid Inverter cost?
A1 SolarStore lists the EG4 Electronics FlexBOSS21 Hybrid Inverter at $4,390.34, new. It is the only store with a current price that we track for this model.
Is the EG4 Electronics FlexBOSS21 Hybrid Inverter an off-grid or a hybrid inverter?
EG4 Electronics describes the EG4 Electronics FlexBOSS21 Hybrid Inverter as a hybrid inverter/charger: it works with solar panels, a battery bank and the utility grid, and it can also run off the grid. EG4 Electronics says it can sell power back to the grid, where your utility allows it.
How many watts can the EG4 Electronics FlexBOSS21 Hybrid Inverter output?
The EG4 Electronics FlexBOSS21 Hybrid Inverter delivers up to 16,000 W of continuous output. Running from the battery alone, it delivers up to 12,000 W.
How much solar can I connect to the EG4 Electronics FlexBOSS21 Hybrid Inverter?
EG4 Electronics lists a maximum solar array of 21,000 W for the EG4 Electronics FlexBOSS21 Hybrid Inverter. Panels connect to 3 separate MPPT inputs, so strings facing different directions can each be tracked on their own. Keep each string below 600 V, and size it to run between 120 and 440 V, where the inverter tracks the panels' best power.
What batteries work with the EG4 Electronics FlexBOSS21 Hybrid Inverter?
The EG4 Electronics FlexBOSS21 Hybrid Inverter runs on a 51.2 V battery bank, and with lithium batteries it works from 40 to 60 V. It charges and discharges the batteries at up to 250 A.
Can the EG4 Electronics FlexBOSS21 Hybrid Inverter start a well pump or an air conditioner?
EG4 Electronics lists a peak output of 24,000 W for the EG4 Electronics FlexBOSS21 Hybrid Inverter for up to 0.5 seconds. Its locked rotor amps (LRA) rating is 195 A. EG4 Electronics says it is powerful enough to start a 5-ton air conditioner. Motors draw a burst of current as they start, so check the LRA on your pump's or air conditioner's nameplate against 195 A.
Can I connect more than one EG4 Electronics FlexBOSS21 Hybrid Inverter?
Yes. EG4 Electronics lists up to 16 units in parallel. At 16,000 W each, that is up to 256,000 W of continuous output.
Can I install the EG4 Electronics FlexBOSS21 Hybrid Inverter outdoors?
Yes. EG4 Electronics rates the EG4 Electronics FlexBOSS21 Hybrid Inverter's enclosure NEMA 4X, a rating for enclosures made to stand up to rain, hose-directed water and corrosion outdoors.
How much does the EG4 Electronics FlexBOSS21 Hybrid Inverter weigh?
The EG4 Electronics FlexBOSS21 Hybrid Inverter weighs 121 lb.
What are the dimensions of the EG4 Electronics FlexBOSS21 Hybrid Inverter?
The EG4 Electronics FlexBOSS21 Hybrid Inverter measures 30.43 × 22.28 × 11.22 inches (height × width × depth).
Is the EG4 Electronics FlexBOSS21 Hybrid Inverter good value?
At $4,390.34 from A1 SolarStore, the EG4 Electronics FlexBOSS21 Hybrid Inverter (16,000 W) works out to 3.64 W/$: its continuous watts divided by the price. That ranks 14th of 30 among the inverters we track with a verified output rating and a current price (higher is better). Shipping is not included, and the figure does not account for build, efficiency or what comes in the box.
See all 30 inverters in this ranking
| Rank | Product | Rated | Price | Store | Value |
|---|---|---|---|---|---|
| 1 | Renogy 3000W 12V Pure Sine Wave Inverter | 3,000 W | $414.99 | Renogy | 7.23 W/$ |
| 2 | Renogy Pro 12V 3000W Pure Sine Wave Inverter with Bluetooth | 3,000 W | $455.99 | Renogy | 6.58 W/$ |
| 3 | Renogy 3000W 12V Pure Sine Wave Inverter with UPS Transfer Switch | 3,000 W | $461.99 | Renogy | 6.49 W/$ |
| 4 | Renogy Pro 12V 2000W Pure Sine Wave Inverter with Bluetooth | 2,000 W | $333.99 | Renogy | 5.99 W/$ |
| 5 | Renogy 2000W 24V Pure Sine Wave Inverter | 2,000 W | $339.99 | Renogy | 5.88 W/$ |
| 6 | Renogy 3500W 48V Pure Sine Wave Solar Inverter Charger | 3,500 W | $599.99 | Renogy | 5.83 W/$ |
| 7 | Renogy 1000W 12V Pure Sine Wave Inverter | 1,000 W | $175.99 | Renogy | 5.68 W/$ |
| 8 | Renogy 2000W 12V Pure Sine Wave Inverter with UPS Transfer Switch and Built-in Bluetooth | 2,000 W | $364.99 | Renogy | 5.48 W/$ |
| 9 | Renogy 3500W 48V Solar Inverter Charger | 3,500 W | $769.99 | Renogy | 4.55 W/$ |
| 10 | Renogy 3000W 12V Pure Sine Wave High-Frequency HF Inverter Charger | 3,000 W | $666.99 | Renogy | 4.50 W/$ |
| 11 | Renogy Pro 12V 1000W Pure Sine Wave Inverter with Bluetooth | 1,000 W | $222.99 | Renogy | 4.48 W/$ |
| 12 | Renogy 2000W 12V Pure Sine Wave High-Frequency HF Inverter Charger | 2,000 W | $522.99 | Renogy | 3.82 W/$ |
| 13 | Renogy 1000W 12V Pure Sine Wave Inverter with UPS Transfer Switch | 1,000 W | $269.99 | Renogy | 3.70 W/$ |
| 14 | EG4 Electronics FlexBOSS21 Hybrid Inverter | 16,000 W | $4,390.34 | A1 SolarStore | 3.64 W/$ |
| 15 | Renogy 3000W 12V Pro Pure Sine Wave Inverter with EcoSleep Mode | 3,000 W | $824.99 | Renogy | 3.64 W/$ |
| 16 | Renogy 2000W 12V Pure Sine Wave Inverter Charger w/ LCD Display | 2,000 W | $595.99 | Renogy | 3.36 W/$ |
| 17 | EG4 Electronics FlexBOSS18 Hybrid Inverter | 13,000 W | $3,879.57 | A1 SolarStore | 3.35 W/$ |
| 18 | Sol-Ark 5K-1P-N Hybrid Inverter | 4,800 W | $1,499.92 | A1 SolarStore | 3.20 W/$ |
| 19 | EG4 Electronics 6000XP Off-Grid Inverter | 6,000 W | $1,878.90 | A1 SolarStore | 3.19 W/$ |
| 20 | Renogy REGO 12V 3000W Pure Sine Wave Inverter Charger w/ LCD Display | 3,000 W | $989.99 | Renogy | 3.03 W/$ |
| 21 | Sol-Ark 30K-3P-208V Commercial Hybrid Inverter | 30,000 W | $10,899.33 | A1 SolarStore | 2.75 W/$ |
| 22 | EG4 Electronics 12kPV Hybrid Inverter | 8,000 W | $2,923.10 | A1 SolarStore | 2.74 W/$ |
| 23 | MidNite Solar Little Rosie MNLR4548RE Inverter/Charger | 4,500 W | $1,709.36 | A1 SolarStore | 2.63 W/$ |
| 24 | Sol-Ark Limitless 18K-2P-LV Hybrid Inverter | 18,000 W | $6,999.32 | A1 SolarStore | 2.57 W/$ |
| 25 | EG4 Electronics 18kPV Hybrid Inverter | 12,000 W | $4,699.08 | A1 SolarStore | 2.55 W/$ |
| 26 | Sol-Ark Limitless 15K-2P-N Hybrid Inverter | 15,000 W | $6,099.15 | A1 SolarStore | 2.46 W/$ |
| 27 | MidNite Power MN15-12KW-AIO Hybrid Inverter/Charger | 11,400 W | $5,650.23 | A1 SolarStore | 2.02 W/$ |
| 28 | Sol-Ark Limitless 12K-2P-N Hybrid Inverter | 9,000 W | $4,699.50 | A1 SolarStore | 1.92 W/$ |
| 29 | OutBack Power VFXR3648A Inverter/Charger | 3,600 W | $2,527.44 | A1 SolarStore | 1.42 W/$ |
| 30 | Magnum Energy MSH3012RV-L RV Inverter/Charger | 3,000 W | $2,538.95 | A1 SolarStore | 1.18 W/$ |
Prices checked Oct 1, 2026. Lowest current new price per product, shipping not included.
What warranty does the EG4 Electronics FlexBOSS21 Hybrid Inverter have?
EG4 Electronics advertises a 10-year warranty for the EG4 Electronics FlexBOSS21 Hybrid Inverter. Check EG4 Electronics's warranty terms before you buy.
Show 10 more questions
Is the EG4 Electronics FlexBOSS21 Hybrid Inverter in stock?
A1 SolarStore lists the EG4 Electronics FlexBOSS21 Hybrid Inverter as in stock. Stock can change, so confirm it at checkout.
How does the EG4 Electronics FlexBOSS21 Hybrid Inverter compare with the Sol-Ark Limitless 15K-2P-N Hybrid Inverter?
The EG4 Electronics FlexBOSS21 Hybrid Inverter delivers 16,000 W of continuous output, and the Sol-Ark Limitless 15K-2P-N Hybrid Inverter delivers 15,000 W of continuous output. At their lowest tracked new prices, the EG4 Electronics FlexBOSS21 Hybrid Inverter is $4,390.34 at A1 SolarStore and the Sol-Ark Limitless 15K-2P-N Hybrid Inverter is $6,099.15 at A1 SolarStore. That is 3.64 W/$ for the EG4 Electronics FlexBOSS21 Hybrid Inverter and 2.46 W/$ for the Sol-Ark Limitless 15K-2P-N Hybrid Inverter. See the Sol-Ark Limitless 15K-2P-N Hybrid Inverter page for its offers and specs.
How does the EG4 Electronics FlexBOSS21 Hybrid Inverter compare with the Sol-Ark Limitless 18K-2P-LV Hybrid Inverter?
The EG4 Electronics FlexBOSS21 Hybrid Inverter delivers 16,000 W of continuous output, and the Sol-Ark Limitless 18K-2P-LV Hybrid Inverter delivers 18,000 W of continuous output. At their lowest tracked new prices, the EG4 Electronics FlexBOSS21 Hybrid Inverter is $4,390.34 at A1 SolarStore and the Sol-Ark Limitless 18K-2P-LV Hybrid Inverter is $6,999.32 at A1 SolarStore. That is 3.64 W/$ for the EG4 Electronics FlexBOSS21 Hybrid Inverter and 2.57 W/$ for the Sol-Ark Limitless 18K-2P-LV Hybrid Inverter. See the Sol-Ark Limitless 18K-2P-LV Hybrid Inverter page for its offers and specs.
Can the EG4 Electronics FlexBOSS21 Hybrid Inverter work as a UPS during a power outage?
Yes. In a power outage the EG4 Electronics FlexBOSS21 Hybrid Inverter switches to battery power in 20 ms or less.
Can I use the EG4 Electronics FlexBOSS21 Hybrid Inverter in cold weather?
The EG4 Electronics FlexBOSS21 Hybrid Inverter is rated to run from -25 °C (-13 °F) to 60 °C (140 °F).
How efficient is the EG4 Electronics FlexBOSS21 Hybrid Inverter?
EG4 Electronics lists a CEC weighted efficiency of 97% for the EG4 Electronics FlexBOSS21 Hybrid Inverter. CEC weighted efficiency averages an inverter's efficiency across typical power levels, so it is the usual figure for comparing inverters.
Is the EG4 Electronics FlexBOSS21 Hybrid Inverter certified to connect to the grid?
EG4 Electronics lists the EG4 Electronics FlexBOSS21 Hybrid Inverter as certified to UL1741, SA, SB. UL 1741 is the US safety standard for inverters that connect to the grid, and the SA and SB supplements cover the grid-support functions many utilities require. It also has built-in rapid shutdown for rooftop solar (NEC 690.12).
What AC voltage does the EG4 Electronics FlexBOSS21 Hybrid Inverter output?
EG4 Electronics lists an AC output voltage of 240 V for the EG4 Electronics FlexBOSS21 Hybrid Inverter.
What phase is the EG4 Electronics FlexBOSS21 Hybrid Inverter?
EG4 Electronics describes the EG4 Electronics FlexBOSS21 Hybrid Inverter as a split-phase inverter.
What is the manufacturer part number of the EG4 Electronics FlexBOSS21 Hybrid Inverter?
Our catalog lists the manufacturer part number (MPN) of the EG4 Electronics FlexBOSS21 Hybrid Inverter as IV-16000-HYB-AW-FX.
Similar inverters from other brands
Published products only. Same category, different brand, similar size and output. Ordered by how close they are, never by price or by who pays us.
Compare it with another inverter
Open the comparison with the EG4 Electronics FlexBOSS21 Hybrid Inverter already loaded, then pick another inverter to compare side by side.
Compare the EG4 Electronics FlexBOSS21 Hybrid InverterHow the comparison works
Solar Gear Scout matches exact hardware first. An offer can win only when its condition, price, stock, freshness and quantity fit this request. Delivered-price comparison also needs a known shipping quote for the destination and purchase quantity.
Current offers
Compare the same exact product across merchants. Freshness, minimum quantities, condition and known shipping remain visible instead of being folded into a misleading headline price.
Solar Gear Scout may earn a commission if you buy through links on this page. Commissions never change how offers are ranked. Read our disclosure.
Ready to buy the EG4 Electronics FlexBOSS21 Hybrid Inverter?
Each store shows its own current price.
View at A1 SolarStoreAffiliate links: we may earn a commission. Details