Custom Battery Adapters

For sale is an original, 3D-printed adapter that allows you to replace the Energizer 523 battery used by early model Apple Macintosh computers with three much more affordable and easy to source LR44 button batteries.

The Energizer 523 (also known as the PX21, A133, EN133A and PC133A, and sometimes substituted for by a 3LR50 battery pack) was used by the original 128K, the 512K and the Plus Macintoshes to preserve their PRAM settings across sessions, however it — and this adapter — may be used in any setting that calls for a 4.5V approx. 16.5mm diameter x 49mm high battery.

Adapters are printed in smaller batches (current stock consists primarily of yellow adapters plus a couple of orange ones) and come with an initial set of three LR44 batteries so it'll be ready to use 'out of the box', so to speak.

Shipping will be via DHL or Deutsche Post (and for international buyers, multiple units will be shipped together and at-cost, despite what eBay's shipping calculator might estimate). Please note that this is a private sale and, as such, no guarantee is provided, nor will returns be accepted.

  • Last modified: 2021-11-19 15:08
  • by Peter