Foolproof Reveals. There are all sorts of devices for marking reveals, but few are as simple and easy to use as a TrimMaster. This double-sided aluminum gauge is sold in sets of two: You use the smaller size for tracing 1/8-inch and 1/4-inch reveals, and the larger size for 3/8-inch and 1/2-inch reveals. Both fit easily in a tool pouch and are sold online for about $15. Farese Tools, 845/832-9056, faresetools.com