A long service life with a guaranteed high cell voltage thanks to a patented cathode technology makes frequent battery changing redundant and promises the best sound. As with any "zinc-air" hearing aid battery that is "air activated", it is highly recommended that you wait at least 60 seconds after you remove the Protective Tab before turning on your hearing aid. This will activate the battery and you will get the most out of it. These items are not refundable once opened. You know you are buying safe, original replacement parts and batteries. Thank you. Bulb Voltage: 1 volts