Use the R3 (1/8”) cutting die with the CornerMaster 7 Corner Rounder. Designed to cut up to 3” of stock at a time, the R3 (1/8”) cutting die can be used to trim the sharp corners of your covers, postcards, business cards, invitations and more. It works with all standard materials such as paper, PVC, polyester and other paper or plastic based products. Dies for the CornerMaster 7 are also available in 1/16”, 5/32”, 3/16”, 1/4", 9/32”, 5/16”, 3/8” and 7/16” radii - these interchangeable dies are quick and easy to switch out.