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Cylindrical Ni-MH battery, green wrap, 46mm long, 11mm diameter

Estry

Estry MDR-RF820 standard battery Ni-MH 700mAh 1.2V 1-pack

SKU CH-D4GC-Y8D6A MPN MDR-RF820

Ni-MH replacement battery delivers 700 mAh at 1.2 V for compatible Sony headphone models

  • TypeBatteries
  • Battery Pack1-pack
  • Battery TypeNi-MH
  • Battery Capacity700mAh
  • Battery Voltage1.2
  • Direct replacement for original headset battery
  • 700 mAh Ni-MH delivers reliable cordless runtime
  • Built-in protection guards against overcharge and short circuits
  • Certified to ISO 9001, RoHS, CE, UN 38.3 and MSDS
  • Compact 46.05 × 11.3 mm pack weighs just 36.0 g

Direct replacement for Sony headphone packs

This Estry Ni-MH cell matches the original BP-550 specification at 700mAh and 1.2V. It fits the MDR-RF820, MDR-RF850R, MDR-RF920RK and other listed wireless headphone models. The single pack restores runtime without modifying the charging cradle.

Upgrade from depleted original cells

When the factory pack no longer holds a charge through a full listening session, this 0.84Wh replacement returns the rated capacity. The jump is worth it if the headphones still sound good but run time has dropped below a useful level.

Steady output during long sessions

Ni-MH chemistry delivers a flat discharge curve so volume stays consistent over hours of use. Built-in overcharge, over-discharge and short-circuit protection prevents voltage sag that can cut audio prematurely.

Highlights

  • Direct replacement for original headset battery
  • 700 mAh Ni-MH delivers reliable cordless runtime
  • Built-in protection guards against overcharge and short circuits
  • Certified to ISO 9001, RoHS, CE, UN 38.3 and MSDS
  • Compact 46.05 × 11.3 mm pack weighs just 36.0 g

Specifications

TypeBatteries
Battery Pack1-pack
Battery TypeNi-MH
Battery Capacity700mAh
Battery Voltage1.2

Questions about this item

What are the dimensions of the Estry MDR-RF820 battery so I can check it fits my headset?

The battery measures 46.05 x 11.3 x 11.3 mm and weighs 36.0 g.

How do I install the battery and what is the common mistake to avoid?

Open the compartment, match the polarity markings, and insert the pack; the common mistake is reversing the positive and negative contacts.

When will the Ni-MH 700 mAh pack need replacing and how do I know?

Replace it when the headset runtime drops noticeably below the original 0.84 Wh capacity; the pack is certified to ISO9001, RoHS, CE, UN38.3 and MSDS standards.

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