The Stage 2 kit for the Nerf Retaliator replaces all of the working parts that come under high levels of stress during use. The parts in our Stage 2 Retaliator kit are produced out of high strength reinforced polymer to allow the use of heavier aftermarket springs without having to worry about breaking your blaster. The breech has been redesigned to reduce dead space and give you a better seal against the dart. The plunger rod and bolt sled have been engineered to handle the increased power of our 5kg spring and will not break under heavy use. Our breech is compatible with the stock dart door as well as the Unleashed Solid: Retaliator Stage 3 Sealed Breech Chamber. WARNING - Some of our products may contain plastic wrapping and small metal parts that could present a choking hazard in young children. Product not intended for children under 8 years of age. Increasing the firing velocity of your blaster can result in injuries if not used with the proper respect. Have fun, but remember to use your blaster responsibly. Neither Orange Mod Works nor Hasbro, Inc. can be held responsible for injuries incurred due to careless blaster use. Orange Mod Works strongly suggests the use of safety glasses during use of your modified blaster.