Watch Battery, Camera Battery, Button Cell Battery, 20mAh, Silver Oxide 1.6V
From Amazon
'"Silver Oxide Button Cell Battery VARTA 14501315 V315 Silber Pack
Conrad Electronic
Varta Button cell SR67, SR716 1.55 V 1 pc(s) 20 mAh Silver oxide SILVER Coin V315/SR67 NaBli 1
BatteryUpgrade
Varta V315 / SR67 / 315 Coin cell battery (Amount 1)