This factory magazine comes standard with the 21-round P365-FUSE model. This magazine will also work with ALL 9mm P365 models including the standard, X, XL, XMACRO, and AXG-LEGION. This magazine features rear witness holes to confirm loaded capacity, an orange follower that makes it easy to identify when unloaded, and a black baseplate. The baseplate is designed to be seated at the bottom of P365-XMACRO (AXG LEGION & FUSE) size grip modules. There will be a gap when seated in P365 Standard, P365X, and P365-XL size grip modules. Compatible with all 9mm P635 models including: P365 Standard P365X P365-XL P365-XMACRO P365-AXG LEGION P365-FUSE Product Specifications Manufacturer: Sig Sauer Model: P365 Caliber: 9 MM Magazine Capacity: 21 Rounds Additional Features: Black Baseplate, Double Stack