The Hostile AEG Raze Full Steel Piston with Piston Head #4R is a factory replacement piston assembly designed specifically for Hostile Raze series AEG rifles. Featuring a durable full steel rack and pre-installed piston head, this complete assembly is manufactured to factory specifications for reliable compression, smooth gearbox cycling, and long-lasting performance. An ideal replacement for worn or damaged piston assemblies during maintenance or gearbox repairs.