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Two black rectangular 12V lead-acid battery cartridges in a 2 pack

PowerWarehouse

PowerWarehouse 2XRBC2SLA29 UPS Replacement Battery 2 Pack

SKU CH-2C5H-WNAJ6

Two 12 V lead-acid cartridges replace APC Back-UPS BK400B batteries

  • CompatibilityFits: APC Back UPS BK400B
  • Compatible with APC Back UPS BK400B
  • 12 V lead-acid cartridge #2 design
  • Two batteries included for full replacement
  • 100 % compatibility guaranteed by manufacturer

Replacement Battery for APC Back UPS BK400B

This 2-pack supplies 12V lead-acid cartridges built to match the original equipment in the APC Back UPS BK400B. Each unit is guaranteed 100% compatible so the UPS regains its rated runtime without modification. The pair covers a complete swap for the BK400B's internal battery set.

When a full battery refresh is worth it

Replace both cells when the UPS reports a battery fault, runtime drops below usable levels or the original set reaches the end of its service life. A single fresh cartridge will not balance the load, so the dual pack restores proper performance. Buyers needing a different voltage, form factor or a higher-capacity upgrade should look elsewhere.

Highlights

  • Compatible with APC Back UPS BK400B
  • 12 V lead-acid cartridge #2 design
  • Two batteries included for full replacement
  • 100 % compatibility guaranteed by manufacturer

Specifications

BrandPowerWarehouse
Model2XRBC2SLA29
CompatibilityFits: APC Back UPS BK400B

Questions about this item

Will the 12V cartridge fit inside the APC Back UPS BK400B without modification?

The 12V cartridge is built as a direct replacement for the APC Back UPS BK400B, so it slides into the existing battery compartment with no cutting or drilling required.

What is the correct order for connecting the two cartridges during installation?

Disconnect the UPS from mains power, remove the old cartridge, insert the first 12V unit, attach its leads, then repeat with the second unit before restoring power.

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