Ruger Complete AR Lower Specifications Manufacturer: Ruger Model: Complete AR Lower Type: AR-15 Lower Receiver Caliber: Multi-Cal Material: 7075-T6 Forged Aluminum Finish: Type III Hardcoat Anodized Stock: Magpul DT Carbine Collapsible Grip: Magpul MOE-K2 Trigger: Ruger Elite 452 AR-Trigger / Two-Stage / 4.5 lb. Pull Buffer Tube: Mil-Spec Includes: Buffer Tube / Carbine Buffer / Recoil Spring Length of Pull: 10.75 in. to 14 in. Overall Length: 15.38 in. to 18.68 in. Height: 6.75 in. Weight: 2.2 lbs. Compatibility: AR-15-Pattern Upper Receiver Assemblies