Lyman's Brass Smith Die Wrench fits all Lyman die nuts, including die body, expander plug, seating screw, and decapping rod lock nuts. This includes the 1" lock nuts used on Lyman Pro dies as well as Dillon dies. Made of rust resistant stainless steel, the closed end design offers added strength with thinner side walls allowing easier fit between dies. The 5 openings accommodate the following size nuts: 1 3/16" - Lyman and RCBS hex style die lock nuts 1" - Lyman Pro and Dillon hex die lock nuts 3/4" - Lyman expander plug lock nuts 5/8" - Lyman seating screw lock nuts 3/8" - Lyman decapping rod lock nuts