Px640 hm-n copper battery adapter for vintage film cameras

PX640 (HM-N) Copper Battery Adapter Price: 1 Adapter – €16 2 Adapters – € 24 The PX640 (HM-N) Battery Adapter is a precision-machined mechanical spacer designed for vintage film cameras and exposure meters that originally used discontinued PX640 mercury batteries. It allows modern button cell batteries to fit correctly inside the original battery compartment while ensuring stable and reliable contact. Made from solid copper, the adapter offers excellent conductivity and long-term durability. It works purely as a mechanical size adapter and does not change or reduce the voltage of the inserted battery. Compatible battery options: • 675 Zinc-Air batteries – closest match to original 1.35V mercury cells for accurate light meter performance • LR44 / SR44 batteries – widely available 1.5V option for cameras that tolerate slight voltage differences Models requiring TWO adapters include Yashica Electro 35 series, Olympus 35 series, Minolta Hi-Matic series, Canon Canodate series, Fujica Date series, and Ricoh Elnica series. Models requiring ONE adapter include Yashica Electro 35 FC and Pentax Spotmeter series.