GunsModify Steel CNC Hammer Housing Marui G17 GBB Slide Stop Semi Automatic Airsoft GBB CO2 Pistol Semi Automatic Airsoft GBB CO2 Pistol Item Weight (gram) 306 Major Color Silver Length 221mm Blow Back Yes Hop up Fixed Shooting Mode Semi Automatic Magazine Capacity 16 Bullet Type 6mm BB Pistol Power Source Electric (Battery Cell) Power (Muzzle Velocity) 190 FPS Manufacturer Tokyo Marui TM Package Includes (1) Tokyo Marui Combat Delta SILVER EBB Airsoft Pistol This new Steel CNC hammer housing from Guns Modify is designed for Tokyo Marui G17 GBB pistols and is constructed with CNC Steel The enhanced structure makes it able to withstand co2 pressure and will be a must have item if you plan to upgrade your G17 to take co2 magazines