🔄
Skip to content

No Sales Tax 💵 Beat-Anyone Price Match 💲 Free Parts for Life 🛠️ Free Shipping on Most Items 📦

No Sales Tax 💵 Beat-Anyone Price Match 💲 Free Parts for Life 🛠️ Free Shipping on Most Items 📦

No Sales Tax 💵 Beat-Anyone Price Match 💲 Free Parts for Life 🛠️ Free Shipping on Most Items 📦

No Sales Tax 💵 Beat-Anyone Price Match 💲 Free Parts for Life 🛠️ Free Shipping on Most Items 📦

No Sales Tax 💵 Beat-Anyone Price Match 💲 Free Parts for Life 🛠️ Free Shipping on Most Items 📦
Facebook Instagram LinkedIn Pinterest
About Us Contact Us Contact Form Privacy Policy Terms of Service FAQ

📞Speak with the Experts📞

EG4 FlexBOSS21 & GridBOSS Bundle

EG4 FlexBOSS21 Inverter & EG4 Gridboss Bundle | 21kW PV Input | 48V Split Phase

SKU BNDL-E00019-2
Save $951.02
$7,285.99
$6,334.97
System Size
No sales tax: save about $475 vs. the 7.5% U.S. average sales tax rate. Why?
Indiana orders are taxed. DE, MT, NH and OR have no state sales tax.
Availability: Translation missing: en.general.icons.icon_check_circle icon Only 10 left!

✅ FREE REPLACEMENT PARTS FOR LIFE ⚙️

Find a better price somewhere else?

Well... we will BEAT it. Call us today to get the best price in the market!

Call/Text Us: 1-888-855-7286
Live Chat With an Expert

  • US Based Authorized EG4 Dealer

    Full manufacturer warranty included

  • 4-5 Day Freight Delivery + No Sales Tax

    More savings on every purchase and ships in 4-5 business day

  • 30-Day Returns & Price Beat Guarantee

    Simple returns + best price guaranteed

  • Post-Purchase Customer Support

    Dedicated help whenever you need it


ESTIMATED DELIVERY BETWEEN

Order within to get it by the earliest date.


EG4 FlexBOSS21 Inverter & EG4 Gridboss Bundle | 21kW PV Input | 48V Split Phase

 Placeholder Image

EG4 FlexBOSS21 All-in-One Hybrid Solar Inverter

The EG4 FlexBOSS21 hybrid solar inverter is a flexible 48V split-phase inverter/charger that delivers the reliable power of the 18kPV with added adaptability. It is powerful enough to start a 5-ton AC unit and supports 21kW of PV input. With the ability to parallel up to 10 units, the FlexBOSS21 achieves an impressive total continuous output of 160kW using PV input. Equipped with three MPPTs, it provides optimal solar management, while the enhanced EG4 monitoring software offers complete remote control, including mobile alerts and remote settings adjustments. Its integration with GridBOSS ensures comprehensive management of the entire Energy Storage System (ESS).

EG4 GridBOSS Micro-Grid Interconnection Device (MID)

The EG4 GridBOSS MID streamlines your Energy Storage System (ESS) by combining up to 10 components into one robust unit. It is designed for seamless integration with utilities, generators, inverters, and loads, providing centralized control, straightforward installation, and real-time remote monitoring.

Kit Type: Residential

Off Grid Applications: Standard Home System (Off-Grid Homes, Cabins, Homesteads)

Hybrid Applications: Standard Home System (3-4 Bedrooms)

EG4 FlexBOSS21 Hybrid Inverter | 48V Split Phase | 21kW PV Input

The EG4 FlexBOSS21 is a versatile 48V split-phase, hybrid inverter/charger that offers the same dependable power as the 18kPV with enhanced flexibility. Powerful enough to start a 5-ton AC unit, the FlexBOSS21 supports 21kW of PV input. Capable of paralleling up to 10 units together, the FlexBOSS21 has an impressive total output of 160kW. Three MPPTs give users optimal control over their solar needs, while the updated EG4 monitoring software allows for convenient total remote management, complete with mobile notifications and remote setting. Seamless interaction with GridBOSS gives users control over their entire Energy Storage System (ESS).

Features:

  • Flexible Power Options: Operate off-grid, with grid support, or sell excess power back to the grid.
  • High PV Input Voltage: Supports up to 600V DC, allowing reduced cable sizes.
  • Smart Connectivity: Remote access with Wi-Fi and closed-loop communication with compatible batteries.
  • Safety-First Design: Includes rapid shutdown, ground fault monitoring, arc-fault protection, and robust safety certifications.
  • CEC Solar Equipment Listing
 Placeholder Image

EG4 GridBOSS Micro-Grid Interconnection Device (MID)

The EG4 GridBOSS MID simplifies your Energy Storage System (ESS) by consolidating up to 10 components into a single, powerful unit. Designed to seamlessly connect utilities, generators, inverters, and loads, it offers centralized control, easy installation, and real-time remote monitoring.

Features:

  • One-Point ESS Control: Connect and manage utility, inverters, generator, and loads from a single device.
  • Reduced Complexity: Replace breakers, transfer switches, and more with one compact solution.
  • Smart Load & Power Shedding: Automate power management to optimize battery performance.
  • 200A Service Entrance: Reliable with a 22 kAIC main breaker for powerful service integration.
  • Real-Time Monitoring: Access and adjust settings remotely via the EG4 app or monitoring system website.
  • Configurable Breakers: Supports one generator up to 125A, 3 hybrid inverters up to 90A each, and 4 smart ports ranging from 60A to 125A.
 Placeholder Image

What's Included

Everything you need is included with your product.
  • 1 x EG4 FlexBOSS21 Hybrid Inverter | 48V Split Phase | 21kW PV Input
  • 1 X EG4 GridBOSS MID | 200A Service Entrance
  • User Manuals

EG4 FlexBoss Specifications
Specification Details
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

EG4 GridBOSS Specifications
Specification Details
Communication Interface RS485/Wi-Fi/CAN
Internal Bus Rating 350A
Internal Fuse Rating 315A
Operating Altitude <6561 ft (<2000 m)
Relative Humidity 0 100%
Outdoor Rating NEMA 3R
Operating Ambient Temperature Range -40°F - 140°F (-40°C - 60°C)
Product Dimensions (HxWxD) 31.5—19.7—7 in (800—500—178 mm)
Unit Weight 55 lbs. (25 kg)
Standard Warranty 10-year standard warranty

Frequently-Asked Questions

Can the EG4 FlexBOSS21 operate both off-grid and grid-tied?

Yes! The FlexBOSS21 is a hybrid inverter, allowing full off-grid independence or grid-tied operation with battery backup for enhanced energy flexibility.

What is the function of the EG4 GridBoss system?

The GridBoss intelligently manages loads by prioritizing solar and battery power before utilizing grid energy, optimizing efficiency and cost savings.

Can I expand my system for more power?

Yes! The FlexBOSS21 supports parallel operation, allowing users to stack multiple units for greater energy needs.

Does it support remote monitoring?

Absolutely! The Wi-Fi and RS485 connectivity allow real-time monitoring and control via the EG4 app.

Manual

Shipping is FREE on most items to customers within the 48 Contiguous States and the District of Columbia. We do not ship to Alaska, Hawaii, or any outlying islands and territories.

Heavy items ship by LTL freight with free liftgate service. Freight is FREE to IN, OH, PA, MI, IL, KY, WV, WI, IA, MO, TN, DE, MD, NJ, NY, VA, DC, CT, MA and VT. Everywhere else in the lower 48, freight is FREE on orders of $4,000 or more. Below $4,000, one flat freight rate covers the whole order: $149 when your freight items weigh under 150 lb in total (most inverters and single batteries) or $299 at 150 lb and up (wall-mount batteries, cabinets, refrigerators). Commercial battery systems over 1,000 lb: email support@kratopower.com with your ZIP for a freight price. Your shipping cost always shows at checkout before you pay.

Processing time for orders is 1 business day

Shipping time for orders is 4-5 business days


Want to know more about our Returns Policy? Read more here.

Want to know more about our Shipping Policy? Read more here.

We get it. You've got a lot of choice when it comes to online retailers. Here's why we think you should shop with us at Krato Power.

  • Family Owned & Operated. Ask for Alex (Owner) at any time!
  • 4-5 Day Free Shipping on most items to the 48 Contiguous States and the District of Columbia. Freight items include free liftgate service and ship free to 19 states + DC and on orders of $4,000+; elsewhere freight is a flat $149 or $299, shown at checkout before you pay.
  • NO Sales Tax except for IN
  • Secured Purchase. All Customer data is secured with SSL Encryption
  • 30-Day Returns. Start a return within 30 days of delivery. See our return policy for details.
  • Exceptional Customer Service. Check out our About Us page.
  • Call or Text Us - We are really here! (In the USA). 1-888-855-7286
In Stock and Ready To Ship

All of our items are in stock and ready to ship. All items ship within 1 business day.

Top Customer Service

We have excellent customer service. Questions? Call us at 1-888-855-7286

30-Day Returns

30-Day Easy Return Policy

Price BEAT Guarantee

Found a better price? We will BEAT it!

Schedule a Consultation

  • Still interested but want to talk at a diferent time?
  • Schedule a consultation here for later!
Book a Consultation
Call to Order: +1 888 855 7286
Description

EG4 FlexBOSS21 Inverter & EG4 Gridboss Bundle | 21kW PV Input | 48V Split Phase

 Placeholder Image

EG4 FlexBOSS21 All-in-One Hybrid Solar Inverter

The EG4 FlexBOSS21 hybrid solar inverter is a flexible 48V split-phase inverter/charger that delivers the reliable power of the 18kPV with added adaptability. It is powerful enough to start a 5-ton AC unit and supports 21kW of PV input. With the ability to parallel up to 10 units, the FlexBOSS21 achieves an impressive total continuous output of 160kW using PV input. Equipped with three MPPTs, it provides optimal solar management, while the enhanced EG4 monitoring software offers complete remote control, including mobile alerts and remote settings adjustments. Its integration with GridBOSS ensures comprehensive management of the entire Energy Storage System (ESS).

EG4 GridBOSS Micro-Grid Interconnection Device (MID)

The EG4 GridBOSS MID streamlines your Energy Storage System (ESS) by combining up to 10 components into one robust unit. It is designed for seamless integration with utilities, generators, inverters, and loads, providing centralized control, straightforward installation, and real-time remote monitoring.

Kit Type: Residential

Off Grid Applications: Standard Home System (Off-Grid Homes, Cabins, Homesteads)

Hybrid Applications: Standard Home System (3-4 Bedrooms)

EG4 FlexBOSS21 Hybrid Inverter | 48V Split Phase | 21kW PV Input

The EG4 FlexBOSS21 is a versatile 48V split-phase, hybrid inverter/charger that offers the same dependable power as the 18kPV with enhanced flexibility. Powerful enough to start a 5-ton AC unit, the FlexBOSS21 supports 21kW of PV input. Capable of paralleling up to 10 units together, the FlexBOSS21 has an impressive total output of 160kW. Three MPPTs give users optimal control over their solar needs, while the updated EG4 monitoring software allows for convenient total remote management, complete with mobile notifications and remote setting. Seamless interaction with GridBOSS gives users control over their entire Energy Storage System (ESS).

Features:

  • Flexible Power Options: Operate off-grid, with grid support, or sell excess power back to the grid.
  • High PV Input Voltage: Supports up to 600V DC, allowing reduced cable sizes.
  • Smart Connectivity: Remote access with Wi-Fi and closed-loop communication with compatible batteries.
  • Safety-First Design: Includes rapid shutdown, ground fault monitoring, arc-fault protection, and robust safety certifications.
  • CEC Solar Equipment Listing
 Placeholder Image

EG4 GridBOSS Micro-Grid Interconnection Device (MID)

The EG4 GridBOSS MID simplifies your Energy Storage System (ESS) by consolidating up to 10 components into a single, powerful unit. Designed to seamlessly connect utilities, generators, inverters, and loads, it offers centralized control, easy installation, and real-time remote monitoring.

Features:

  • One-Point ESS Control: Connect and manage utility, inverters, generator, and loads from a single device.
  • Reduced Complexity: Replace breakers, transfer switches, and more with one compact solution.
  • Smart Load & Power Shedding: Automate power management to optimize battery performance.
  • 200A Service Entrance: Reliable with a 22 kAIC main breaker for powerful service integration.
  • Real-Time Monitoring: Access and adjust settings remotely via the EG4 app or monitoring system website.
  • Configurable Breakers: Supports one generator up to 125A, 3 hybrid inverters up to 90A each, and 4 smart ports ranging from 60A to 125A.
 Placeholder Image

What's Included

Everything you need is included with your product.
  • 1 x EG4 FlexBOSS21 Hybrid Inverter | 48V Split Phase | 21kW PV Input
  • 1 X EG4 GridBOSS MID | 200A Service Entrance
  • User Manuals

EG4 FlexBoss Specifications
Specification Details
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

EG4 GridBOSS Specifications
Specification Details
Communication Interface RS485/Wi-Fi/CAN
Internal Bus Rating 350A
Internal Fuse Rating 315A
Operating Altitude <6561 ft (<2000 m)
Relative Humidity 0 100%
Outdoor Rating NEMA 3R
Operating Ambient Temperature Range -40°F - 140°F (-40°C - 60°C)
Product Dimensions (HxWxD) 31.5—19.7—7 in (800—500—178 mm)
Unit Weight 55 lbs. (25 kg)
Standard Warranty 10-year standard warranty

Frequently-Asked Questions

Can the EG4 FlexBOSS21 operate both off-grid and grid-tied?

Yes! The FlexBOSS21 is a hybrid inverter, allowing full off-grid independence or grid-tied operation with battery backup for enhanced energy flexibility.

What is the function of the EG4 GridBoss system?

The GridBoss intelligently manages loads by prioritizing solar and battery power before utilizing grid energy, optimizing efficiency and cost savings.

Can I expand my system for more power?

Yes! The FlexBOSS21 supports parallel operation, allowing users to stack multiple units for greater energy needs.

Does it support remote monitoring?

Absolutely! The Wi-Fi and RS485 connectivity allow real-time monitoring and control via the EG4 app.

Manual
Shipping

Shipping is FREE on most items to customers within the 48 Contiguous States and the District of Columbia. We do not ship to Alaska, Hawaii, or any outlying islands and territories.

Heavy items ship by LTL freight with free liftgate service. Freight is FREE to IN, OH, PA, MI, IL, KY, WV, WI, IA, MO, TN, DE, MD, NJ, NY, VA, DC, CT, MA and VT. Everywhere else in the lower 48, freight is FREE on orders of $4,000 or more. Below $4,000, one flat freight rate covers the whole order: $149 when your freight items weigh under 150 lb in total (most inverters and single batteries) or $299 at 150 lb and up (wall-mount batteries, cabinets, refrigerators). Commercial battery systems over 1,000 lb: email support@kratopower.com with your ZIP for a freight price. Your shipping cost always shows at checkout before you pay.

Processing time for orders is 1 business day

Shipping time for orders is 4-5 business days


Want to know more about our Returns Policy? Read more here.

Want to know more about our Shipping Policy? Read more here.

Why Buy From Us

We get it. You've got a lot of choice when it comes to online retailers. Here's why we think you should shop with us at Krato Power.

  • Family Owned & Operated. Ask for Alex (Owner) at any time!
  • 4-5 Day Free Shipping on most items to the 48 Contiguous States and the District of Columbia. Freight items include free liftgate service and ship free to 19 states + DC and on orders of $4,000+; elsewhere freight is a flat $149 or $299, shown at checkout before you pay.
  • NO Sales Tax except for IN
  • Secured Purchase. All Customer data is secured with SSL Encryption
  • 30-Day Returns. Start a return within 30 days of delivery. See our return policy for details.
  • Exceptional Customer Service. Check out our About Us page.
  • Call or Text Us - We are really here! (In the USA). 1-888-855-7286