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Single 6V 4.5Ah sealed lead-acid battery in plastic casing

RefurbUPS

RefurbUPS Xfinity 300VA 165W U12-40743 ups replacement battery

SKU CH-D0BY-T147Y

A 6 V 4.5 Ah sealed lead-acid battery kit replaces the cartridge in Xfinity 300 VA 165 W UPS units (U12-40743)

  • TypeKit/Package
  • Weight3
  • Compatible with Xfinity 300VA 165W UPS
  • Single 6V 4.5A high-rate discharge SLA battery
  • Factory-fresh cell for reliable backup power
  • Includes step-by-step installation instructions
  • Model U12-40743 ensures exact fit

Compatible Battery Kit for Xfinity 300VA UPS

This replacement battery kit is built for the Xfinity 300VA 165W uninterruptible power supply using part number U12-40743. It supplies a single 6V 4.5A sealed lead-acid cell rated for high-rate discharge. The unit arrives factory fresh and includes comprehensive installation instructions for a straightforward swap.

Sealed Lead-Acid Chemistry Constraints

The 6V 4.5A SLA cell uses valve-regulated lead-acid chemistry, which requires upright mounting and periodic recharging during long storage. Capacity will diminish gradually over several years of float service, and deep discharges shorten overall lifespan. The kit contains one cartridge weighing 3 units, matching the original form factor for direct installation.

Upgrade from Depleted Original Cartridge

This kit replaces a worn-out factory cartridge when runtime has fallen below acceptable levels or the UPS signals a battery fault. The jump is worth it when the existing pack no longer holds sufficient charge to bridge outages for connected equipment. It restores original 300VA 165W backup performance without modifying the host UPS.

Highlights

  • Compatible with Xfinity 300VA 165W UPS
  • Single 6V 4.5A high-rate discharge SLA battery
  • Factory-fresh cell for reliable backup power
  • Includes step-by-step installation instructions
  • Model U12-40743 ensures exact fit

Specifications

BrandUltra
SeriesUltra Batteries
TypeKit/Package
Weight3

Questions about this item

Which Xfinity UPS model does the U12-40743 kit fit?

This kit is built for the Xfinity 300VA 165W UPS and contains one 6V 4.5A sealed lead-acid battery cartridge.

What runtime can I expect from the 165W rating on my Xfinity 300VA unit?

The 165W figure is the UPS output capacity; actual backup time depends on the connected load, battery age and temperature.

What connector standard does the 6V 4.5A cartridge use?

The battery uses the standard F1/F2 faston tabs found on the original Xfinity 300VA cartridge for a direct plug-in swap.

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