We take cryptocurrency — so the coins you hold can buy real hardware.Pay in crypto, spend it on real hardware. Free insured shipping worldwide over $399. Plain, unbranded boxes, sent from Germany.Free insured shipping over $399. Your rate is locked for 30 minutes once checkout opens.Rate locked 30 minutes. Every item sealed, serial-checked and covered by a 24-month warranty.Sealed, 24-month warranty.

Saved items Sign in
Small rectangular Ni-MH battery pack with wire connector, light-coloured plastic casing

Estry

Estry KX-TC1721 3.6V 700mAh standard battery

SKU CH-P5PK-JSJAC MPN KX-TC1721

Replacement Ni-MH battery delivering 3.6 V and 700 mAh for compatible cordless phones

  • Specifications3.6
  • Battery Pack1 Year
  • Exact-fit replacement for Panasonic cordless phones
  • 6 V 700 mAh Ni-MH chemistry matches original spec
  • Built-in overcharge, over-discharge and short-circuit protection
  • Certified to ISO 9001, RoHS, CE and UN 38.3
  • Compact 50.79 x 42.4 x 14.23 mm pack weighs 114.3 g

Replacement battery for Panasonic cordless phones

The Estry KX-TC1721 is a 3.6 V, 700 mAh nickel-metal-hydride pack built to match the original specifications for Panasonic handsets including the KX-TC1721, KX-FPC91, KX-TG2583, KX-TC1750, KX-TC1858, KX-TC1852 and KX-T3845 series. It also replaces part numbers P-P508, KX-A36, P-P501, P-P510, TYPE 21, HHR-P505PA, RCT-3A-C1, HHR-P505, TYPE 1, P-P504 and KX-TCA14. The cell carries ISO 9001, RoHS, CE, UN 38.3 and MSDS certifications.

Drop-in fit with no soldering required

The pack measures 50.79 x 42.4 x 14.23 mm and weighs 114.3 g, matching the factory footprint so it slides into the handset battery compartment without modification. No wiring changes or external chargers are needed; the handset’s own cradle handles charging once the replacement is installed. Buyers whose handset uses a different voltage, capacity or physical layout will need a different pack.

Steady output through repeated charge cycles

Rated at 2.52 Wh, the Ni-MH chemistry delivers a stable 3.6 V nominal voltage across the discharge curve, avoiding the sharp voltage drop that can cause handsets to cut out early. Built-in protection guards against over-charge, over-discharge, over-voltage and short-circuit events, helping the pack maintain usable capacity over a full year of daily charge-and-discharge cycles.

Highlights

  • Exact-fit replacement for Panasonic cordless phones
  • 6 V 700 mAh Ni-MH chemistry matches original spec
  • Built-in overcharge, over-discharge and short-circuit protection
  • Certified to ISO 9001, RoHS, CE and UN 38.3
  • Compact 50.79 x 42.4 x 14.23 mm pack weighs 114.3 g

Specifications

BrandNi-MH
Model700mAh
Specifications3.6
Battery Pack1 Year

Questions about this item

How long will the 700mAh Ni-MH pack last on a single charge under continuous talk time?

The 3.6V 700mAh cell stores 2.52Wh; actual run time depends on the handset's current draw, which varies by model.

Does the battery get hot or make noise during all-day charging?

Ni-MH chemistry runs silently; the pack includes over-charge, over-discharge, over-voltage and short-circuit protection to limit heat build-up.

Which cordless phone models accept the P-P508 / HHR-P505PA pack without modification?

Direct replacements include KX-TC1721, KX-FPC91, KX-TG2583, PQWBTC1461M, KX-TC1750, KX-TC1858, KX-TC1852 and KX-T3845.

Also in this aisle

People compared these

Same shelf, same checkout — eight coins and a 30-minute rate lock.