V-Tac 74220 Valken Battle Machine AEG Mod-M Rifle, Black Full Metal Standard Ratio Gears, Stainless Steel 6mm Oil less Bushings Stainless Steel 6mm Oil less Bushings, Anodized Aluminum Type 1 Cylinder, Full Metal Double O-ring Cylinder Head Full Seal Nozzle w/ Inner O-ring, Ported Piston Head, 7-Metal Tooth Piston Full Metal 1-Piece Hop-Up, Full Metal Spring Guide, Anodized Aluminum 6.05 Inner Barrel 300mm 1 year bulletproof warranty, Compatible with most M4 AEG magazines on the market, Compatible with 8.4v/9.6v NiMh and 7.4v LiPo, Includes (1) Valken Tactical 300rd Polymer RMAG Hi-Cap