The Mark IV is the fourth generation of Ruger's .22 LR Standard pistol, the gun that launched Ruger as a company in 1949. The Mark IV's defining feature over its predecessors is a push-button disassembly mechanism — one button releases the receiver for cleaning without tools, eliminating the notoriously frustrating Mark I/II/III disassembly process. The Standard model has a 4.75-inch barrel and fixed sights. Type: Pistol Action: Semi-Automatic Caliber: .22 LR Capacity: 10 Year introduced: 2016, USA Weight: 33 oz Overall length: 8.5" Status: Active Intended use: Plinking, Target, Training