Glock PA4850201FRMOS: Chambered in 9x19 the G48 MOS features the Glock Slim Mounting Rail for mounting tactical accessories and incorporates elements of the Slimline series such the short trigger distance, a frame with a built-in beavertail, a reversible magazine catch and the incredibly accurate, match-grade Glock Marksman Barrel (GMB) of the Gen 5 series. The G48 Rail also features precision-milled front serrations. The slim magazine has an orange magazine follower for higher visibility and is specifically developed to ensure the 10 rds magazine capacity. Note: The G48 with the Modular Optic System (MOS) does not come with adapter plates.