PRODUCT DESCRIPTION PRODUCT SPECIFICATIONS FN 545 MRD 45ACP BLK 10+1 407C Manufacturer: FN Finish: Black Rate of Twist: 1-in-16" Barrel Length: 4.1" Model: FN 545 MRD Holosun Color: Polymer Frame Black Polymer Polymer Frame UPC: 845737018290 Caliber: 45 ACP Action: Striker Fired Capacity: 10 + 1