Shocker Evolve V2 Low Pressure Firing Assembly Bolt Kit for a Paintball gun. The Shocker's Bolt kit assembly consists of the; Bolt, Bolt Sleeve, and Fire Chamber. The Evolve kits allows for operating pressures down to around 180 psi. This bolt kit only works in sealed body shockers. These include the Nasty, Pre 06 Dynasty, Strange, Octane, Toxic, and TonTon Shockers.