I'm assuming that yer regular bottles are like the one pictured on yer site on the right with the cork stopper at this link - Fergal bottles . I would like one if'n ya ave em. Ana they be 5 ya say?
Ow the ole saying go "Nothin up me sleeve?" Just try and be convincin the mate that be loosin to ya cross the table in cards. on the other hand, it be easy hidin a pistol in there.