Part of the ASG ULTIMATE® Upgrade Series, this non-ported full-volume cylinder is manufactured from 45C cold-drawn seamless steel. Designed for long-barrel AEG setups (451mm – 550mm inner barrels such as M16, AK, and G3 series), it undergoes an Isonite oxide surface treatment to create an ultra-smooth, low-friction internal bore that minimizes O-ring wear. The outer surface features precision CNC ribbed grooving that expands surface area for efficient heat dissipation during rapid cycling, protecting grease lubrication and seal integrity. 100% Tokyo Marui compatible across V2, V3, V6, and V7 gearboxes.