Made of tool steel, this is a quality threading kit in Imperial die holder sizes Shanks for hardened and precisely ground. Comes with 2MT shank . The body has epoxy black finish for a rust free life. The imperial die holder capacity/ sizes are13/16", 1", 1-5/16" & 1-1/2" Inches. These are interchangeable with the body and can be locked through with the body through a allen screw in the cavity at the holding spigot of each holder, so that it does not slip while threading the job. The morse taper parts slides inside the lathe's tailstock & the floating die holder holds the threading die. The handle on the body kept the holder stationary and the threads are being created on the rotating job clamped in the lathe's chuck grip. Each holder is marked with its size details on it for user's reference. Supplied in a styrofoam plastic case for safe life long storage.