BB Retaining Ball for later Crosman V350's, Crosman 3500 and M1. Use with spring CRS350-041, sold seperately. Also used for the Benjamin 392 and 397 safety, etc. This is the mid sized ball of the 3 different balls 0.140" (7/64) diameter used for retaining bbs in the Crosman V350, M1, and V3500. Use with spring CRS350-041.