The Trim Doctor is a tool for manufacturing short case shells such as the 10 gauge 2-7/8" and 12-gauge 2" or 2-1/2". 12 gauge 3-inch cases can be made into 2-3/4" cases, extending the useful life of the shells. Using a case trimmer: A threaded adjustment gauge in the Trim Doctor holds shells in perfect alignment as the old crimp is removed. You will have a fresh, crimpable edge remaining. A regular full cut removes 1/4" at a time (about the same as full fold crimp). A 3" shell becomes a 2-3/4", 2-3/4" become 2-1/2". Two full cuts on a 10 gauge shell produce a 2-7/8" shell. Shell Disassembly Tool - 10 through 28 gauge: Remove the threaded guide. Insert loaded shell into opening. Turn shell while gently pressing on the blade guide, top of shell will cut off cleanly after a few turns and the components can be retrieved, usually including the wad. Made in U.S.A.