A hand operated, carbide cutter easily trims excess material from the bottom barrel lug when fitting custom or factory barrels to 1911 autos. These cutters remove material from the barrel lugs in a parallel fashion, and with the correct height and radius, to help produce the best possible lockup. It is recommended to use the 0.186" cutter first, then progress to the 0.195" cutter if more material needs to be removed. Follow with careful hand fitting to achieve a firm, non-binding barrel-to-slide fit. Start small and check your work often. It is possible, with some slide/barrel combinations, that the 0.195" cutter could remove more material than necessary. Fits all 1911 A Mfg: Brownells SPECS: 1' (2.5cm) diameter knob; 2.07' (5.25cm) long shank. .186' (4.72mm) or .195' (4.95mm) diameter cutters. Complete instructions included.