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FSKE KB440-03H 40V 6Ah Replacement Battery, 2-Pack1 / 6
Product guide

FSKE KB440-03H 40V 6Ah Replacement Battery, 2-Pack

FSKE KB440-03H is a two-pack of rechargeable lithium-ion replacement batteries listed for Kobalt 40V power tools. Each battery is specified at 6 amp-hours, with four LED fuel indicators for checking the charge level. Compatibility depends on the tool and charger model, so compare your model numbers with the listing before buying.

At a glance

  • Two batteries are claimed in the title and feature listing, providing a spare for compatible equipment.
  • The listing specifies 40 volts and 6 amp-hours per battery.
  • Four LED fuel indicators are described, with each light representing 25% of battery power.
  • Compatibility is stated for selected Kobalt 40V tools and chargers. Check the exact model before relying on fit.
Price
$98.99Save 18%

Reference price: $119.99

Price checked: Nov 14, 2026

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Often bought together

Pros and cons

Pros

  • Two-pack format can provide a charged spare while another battery is in use.
  • Four charge-level indicators provide a quick visual estimate of remaining battery power.
  • The listing names several compatible Kobalt 40V tool and charger models.

Technical specifications

11 specifications
Identity
BrandFSKE
ModelKB440-03H
Power and battery
Battery typeLithium Ion
Voltage40 volts
Capacity6 amp_hours
Rated current capacity6000 milliamps
RechargeableRechargeable
Compatibility
Listed tool compatibilityReplacement for Kobalt 40V Battery 6.0Ah, Compatible with Kobalt 40V Cordless Power Tool, for 40V Max Battery KB440-03 KB2540C-06 KB240-03 KRC60
Listed charger modelsKRC60-06, KRC40-06, KRC840-03
Dimensions and installation
Dimensions listed6.69 x 4.33 x 1.97 inches
Weight listed5.6 pounds

What to know before buying

Listing details to confirm

The listing has inconsistent quantity and weight details: the title and feature text claim two batteries, while the battery-count field says one battery is included, and listed battery weight is 2.7 pounds while item weight is 5.6 pounds. Confirm the selected listing's quantity and package details. Compatibility is also stated for specific Kobalt model numbers, so verify your tool and charger model before purchase. The claimed 50% more power than a 4.0 battery and other performance statements are manufacturer claims, not independently confirmed here.

Who is it for?

A good fit for

  • Kobalt 40V tool owners seeking a listed 6Ah replacement and a second battery for rotation.
  • Buyers whose tool and charger model numbers match those named in the compatibility details.

Less suited to

  • Owners of tools or chargers outside the listed compatibility range unless compatibility is confirmed.
  • Buyers who need independently established battery runtime, cycle life, or charging performance.
FSKE KB440-03H 40V 6Ah Replacement Battery, 2-Pack · photo 2
Additional product photo 2

Customer reviews on Amazon

4.4 / 5 · 389 ratings
  • 5 stars75%75%
  • 4 stars9%9%
  • 3 stars4%4%
  • 2 stars3%3%
  • 1 star9%9%

Aggregate customer ratings lean positive, with most recorded ratings in the five-star category, but a meaningful portion are one-star and the spread does not explain the reasons. No written customer feedback is supplied, so the ratings cannot establish performance or compatibility. For buyers, confirming model fit and the advertised two-battery quantity matters more than inferring runtime or reliability from the rating pattern.

Frequently asked questions

How many batteries are included?

The title and feature text describe a two-pack, but the battery-count field says one battery is included. Confirm the quantity on the selected listing before ordering.

Which tools and chargers are listed as compatible?

The listing names selected Kobalt 40V tools, including models KB440-03, KB2540C-06, and KB240-03, and chargers KRC60-06, KRC40-06, and KRC840-03. Check your exact model.

What does the LED indicator show?

The listing describes four fuel indicators, with each light representing 25% battery power. This is a charge-level indication, not a stated runtime estimate.

Is the stated 6Ah capacity independently verified?

No independent measurement is provided. The listing specifies 6 amp-hours and 6000 milliamps as manufacturer claims.

FSKE KB440-03H 40V 6Ah Replacement Battery, 2-Pack · photo 3
Additional product photo 3

Alternative options

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