Tactical Solutions Trail-Lite Integral Adjustable Rear Sight Picatinny Scope Base (Top Rail) easily mounts on your factory Browning Buck Mark pistol and Tatical Solutions Trail-Lite Barrels. Screws included Length 4.97 (uses Standard RUGER Rear Sight Blades see our other listings) We are a Tactical Solutions Dealer. CHECK OUR OTHER LISTINGS FOR MORE GUN STUFF.