This magazine disassembly tool works on standard magazine base plates or floor plates, for 9/40 models 17, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 43X, 48. Does not work on the Model 30 round magazines or extended type base plates