cheers nobby. i dont know what type they are in the link nikey but for that price they probably are zinc air type. these type need air to work and all taped up and a few feet down a rabbit hole, air could get a bit low. i know a few people still use them but for the extra quid or so i know id rather have the real deal that will last and help me do all i can to retreive my ferret when needs be. its the silver oxide you should use and preferably a decent make, i use rayovacs, varta, renata or similar. picked up 10 for about a fiver off ebay a while ago through the best offer thing.
hth,