Regulated Battery Adapters for Older Mercury Cell Light Meters

I offer an adapter for the
Asahi Pentax Spotmeter 21/1 that regulates a 3-volt lithium cell down to the 1.34 volts needed by the spotmeter. Follow this link for more information and ordering information.

All of the adapters are sold. There are no more available and there will be no more built. The frequency of selling an adapter is down to about one every four months, and it is just no longer viable to build more.

  Picture of PX640 adapter

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