Ruger Mark IV, 22/45, Semi-automatic, 22LR, 4.4, Black, Checkered, 10 Rounds, 2 Magazines, Threaded, Adjustable Rear Sight, Polymer, Blued, Optics Ready 40190 The Ruger Mark IV 22/45 features a simple, one-button takedown for quick and easy field-stripping and proper chamber-to-muzzle cleaning. Pressing a button at the back of the frame allows the barrel-receiver assembly to tilt up and off the grip frame without any tools. The cold hammer-forged barrel results in highly precise rifling that delivers exceptional accuracy and longevity.