This SIG P365 12-round 9MM magazines is compatible with all SIG SAUER P365 and P365XL micro-compact, concealed carry pistol models. The magazine features a unique capacity witness hole that remains visible while the magazine is inserted in a standard P365. This allows full capacity status to be verified without removal of the magazine. The installed baseplate leaves no gap when inserted into a standard P365. The 12-round magazines ships with an additional baseplate that can be easily installed to all SERIES P365 models, including the P365XL. The overall length of the magazine is extended an additional 1″ compared to the original 10 round flush fit magazine.