I have an elderly relative staying with me over Christmas. She has a hearing aid, but we have stupidly forgotten to bring her spare batteries with us and the current one is running out. I am pretty sure that I can buy spare batteries from Boots, but can anyone tell me which ones to buy ? I cannot see any identification on the battery itself and all I can find on the hearing aid is Siemens Prisma 2 VC+ Does anyone have any ideas, or is it throat lozenges I should get from Boots to ease our throats after all the shouting we will have to do? Thanks