Martha Stewart Punches work perfectly with card - even heavy embossed cardstock and most paper weights - but do not work very well with thin paper - the punch does not want to release the paper from the body of the punch. We recommend that when you use them, use cardstock - and if they are going to be used with fairly thin paper - the paper should be inserted into the punch WITH some cardstock - you will find this stops all the problems of the paper not being released.