The Kel-Tec SU-16B adds a folding stock to the SU-16 platform, allowing the rifle to fold in half for backpack storage. When folded the rifle measures approximately 18 inches, making it one of the most compact 5.56 semi-automatic rifles available. Type: Rifle Action: Semi-Automatic Caliber: 5.56x45mm Capacity: 10 Year introduced: 2004, USA Weight: 5.1 oz Overall length: 29" Status: Active Intended use: Hiking, Home Defense, Survival