I think a wallet would work better - card holders generally don't have long enough continuous strips of the surface to really get a strap out of. Depending on the size of the watch and strap, two might be possible but not likely. Shoot me an email at [email protected] so we can talk more.I'm interested also. Is a card holder enough material? If not, is a wallet enough material for two? For the $500+ I'd spend on the wallet and considering I wouldn't put this on a high-end piece, I'd like to ideally have two straps.