Nockturnal Shift Universal Easy Off Nock System Red. These lighted nocks offer unparalleled simplicity and reliability featuring an external on/off switch that allows for effortless control. Just slide the switch to turn off the ultra-bright string-activated LED light. With a durable polycarbonate casing these nocks are both waterproof and shockproof ensuring they withstand the toughest conditions. Boasting over 20 hours of battery life the Nockturnal Shift FIT lighted nocks are designed to last. The patented piston-driven contact linear switch activates the light immediately upon string release providing instant illumination. Specifications for Nockturnal Shift Universal Easy Off Nock System: Manufacturer: Nockturnal Fabric/Material: Polycarbonate Weight: 25 grain Features of Nockturnal Shift Universal Easy Off Nock System Super strong clear polycarbonate construction Waterproof and shockproof design Easy on/off light system with external switch More than 20 hours of lithium-powered battery life Package includes three lighted nocks H bushings GT bushings and S bushings Package Contents: Nockturnal Shift Universal Easy Off Nock System Nockturnal NT-830: Shift Universal Easy Off Nock System Red