The Level 1 Starter Kit includes everything you will need to get started training immediately. Each Level 1 Starter Kit includes: Choice of (1) UNIT4 Training Rifle (10.5", 14.5" or 16" barrel) (1) UNIT4 Magazine (300) Marking Rounds (300) Non-Marking Rounds (1) TPAK Re-Stack Assembly Kit MATERIALS & CONSTRUCTION: Lower Receiver Mil-Spec with Rear Receiver QD Swivel Attachment Point. CNC Machined of 7075-T6 Aluminum, Type III Hard Coat Anodized Upper Receiver Mil-Spec with Indexing Marks. CNC Machined of 7075-T6 Aluminum, Type III Hard Coat Anodized Barrel (Outer & Inner) Outer: Chrome Moly Vanadium Steel, Mil-Spec Heavy Phosphate Coated.Inner: Nickel plated, smooth bore, brass tube for 8mm Rounds Muzzle Device Standard Mil-Spec A2 Flash Suppressor, Cerakote Blue Bolt Carrier Group 4140 Low Alloy Steel; Minimal Changes to M16 Profile while allowing for Non-Firearm Certification Sights Sold separately Handguard UNIT Solutions Low Profile M-Lok Handguard Charging Handle Mil Spec with Right Latch Selector Ambidexterous; Safe, semi & full Receiver Extension 6 Position Mil-Spec 7075-T6 Aluminum Buttstock Magpul MOE-SL Carbine Stock Pistol Grip Magpul MOE-SL Pistol Grip SPECIFICATIONS: Caliber 8mm Muzzle Thread 5/8" x 24 TPI (Threads Per Inch) Gas System CO2 Barrel Length 10.5", 14.5" and 16" Magazine UNIT4 Magazine Manufacturer UNIT Solutions