FORPY...i quite like that
any way sorry mate do you mean the little metal rings with tags on that you crush to make em grip your pipe(OOER) or something else? by the replies i thought it must be the metal rings but technically an "o"ring is a rubber washer with a circular cross section like what you have in the pre filter housings on your ro man
.......but i think you are talking about crimps and i use a pair of wire clippers but pincer pliers(aka blacksmith pliers) as posted by william x are probably better ;)what are you trying to connect?