By Lielle ben simon, 15 July, 2016 Forum watchOS and Apple Watch Apps Hi i have a band for apple wotch, but i don't kno if she's 38 or 42 mm.i had boght from eBay, i am not atention for this. how can i to kno this? i filling that is a littel to my hand. tahnks! Options Log in or register to post comments Comments Try the apple watch band Try the apple watch band on your wrist.