Massacre Mod Kit for Nerf Recon This kit includes metal trigger catch, 2x double strength trigger catch springs, reinforcement plate, 5+ kg mainspring (2.5kg stock), polycarbonate bolt sled with pin, polycarbonate breech with o-ring, polycarbonate plunger, and silicone grease. When installed, the Recon shoots 90fps muzzle velocity with up to 65ft range (parallel to ground) and up to 80ft range (30 degrees angled to ground) with streamline darts. With weighted darts, we achieved ranges of 75ft parallel to ground and 90ft 30 degrees angled to the ground. Mod at your own risk! Increasing the spring tension can break or damage stock internal components of your blaster. Blaster not included.