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Rectangular lithium-ion battery pack with dark grey plastic casing, approximately 71.7 by 37.6 by 20.4 millimetres

Estry

Estry Replacement Battery for Righton Retinomax 3 K-Plus 3 RT-121 7.4V 2600mAh

SKU CH-TFJM-BM261

Replacement Li-ion battery for Righton Retinomax 3 and K-Plus 3, 7.4V 2600mAh with overcharge and short-circuit protection

  • Battery capacity2,600 mAh
  • Battery voltage rating7.4
  • Product typeRechargeable Batteries
  • Direct replacement for Righton Retinomax 3 and K-Plus 3
  • 4V 2600mAh Li-ion cell delivers 19.24Wh capacity
  • Built-in overcharge, over-discharge and short-circuit protection
  • Compact 71.7 x 37.6 x 20.4mm form factor weighs 170.0g
  • Certified to ISO9001, RoHS, CE and UN38.3 standards

Righton Retinomax 3 and K-Plus 3 Battery Replacement

This Estry replacement battery is built for the Righton Retinomax 3 and K-Plus 3 handheld devices using part number RT-121. It supplies 7.4V and 2600mAh capacity in a lithium-ion cell. The pack includes overcharge, over-discharge, over-voltage and short-circuit protection. It holds ISO9001, RoHS, CE, UN38.3 and MSDS certifications.

Suits owners needing a direct-fit spare

Clinicians and technicians who rely on the Retinomax 3 or K-Plus 3 for daily measurements will find this a like-for-like power source. It is not for users of other Righton models or devices that require a different voltage, connector or form factor. Buyers who need higher capacity or a different chemistry should look elsewhere.

2600mAh cell delivers 19.24Wh for extended sessions

The 2600mAh rating provides 19.24Wh of energy, supporting long examination periods between charges. Runtime scales with device brightness and measurement frequency; intensive back-to-back use will deplete the pack faster. The 71.7 x 37.6 x 20.4mm footprint fits the original battery bay without modification.

How it compares

Measured against everything we stock in Household Batteries & Chargers, at today’s prices. Recalculated every night.

Price $21.99
Pricier than about 80% of the 10,440 comparable items (median $10.99).

Specifications

Product
Brand nameRighton
Product typeRechargeable Batteries
Power
Battery capacity2,600 mAh
Battery voltage rating7.4

Questions about this item

What device must I already own to use this 7.4V 2600mAh replacement battery?

It is built for the Righton Retinomax 3 and K-Plus 3 handheld autorefractors that take the original RT-121 pack.

Will the 71.7 x 37.6 x 20.4 mm form factor fit the battery compartment of my existing Retinomax 3?

Yes, the dimensions match the factory RT-121 so it slides into the same slot without modification.

How can I confirm the 19.24 Wh Li-ion cell is working correctly after installation?

Power on the Retinomax 3; the device should boot normally and show its usual battery-level indicator without error codes.

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