Hearing Aid Battery, Button Cell Battery, Zinc-air
From Amazon
GP Zinc Air Hearing Aid Batteries | ZA10 (PR70) Yellow, 1.4V, 75mAh, 3.6x5.8mmØ, 6pcs/pack.
Conrad Electronic
GP Batteries Button cell ZA 10 1.4 V 6 pc(s) 90 mAh Zinc air GPZA10F145C6
BatteryUpgrade
GP PR70 / ZA10 Zinc-Air Coin cell battery (6 pcs)