The Tactical Solutions Pac-Lite IV is a replacement upper receiver for Ruger Mk-series pistols, featuring a 6-inch threaded anodized aluminum barrel and integral Picatinny optics rail. The Pac-Lite is not a complete pistol but a drop-in upper that transforms any Ruger Mk II, III, or IV lower into a suppressor-ready target pistol. Type: Pistol Action: Semi-Automatic Caliber: .22 LR Capacity: 10 Year introduced: 2003, USA Weight: 4 oz Status: Active Intended use: suppressed shooting, target shooting, plinking