Nockturnal Shift Red/Green Strobing Lighted Arrow Nocks - 2 Pack - Advancing the lighted nock design by which all others are judged, Nockturnal Shift FIT lighted nocks take the simplicity and reliability of the world's most dependable and user-friendly lighted nock to an entirely new level. Thanks to the external on/off switch the process of turning an ultra-bright, string activated Nockturnal lighted nock off has never been easier. Just slide the switch and the nock turns off. It's that simple! With 20+ hours of long-lasting battery life and a durable design these nocks are built to last and perform like none other. Constructed of an ultra-strong, impact resistant, polycarbonate casing that protects the super-bright LED lights Shift nocks deliver on what users have come to expect from Nockturnal lighted nocks. The patented, string-activated, piston-driven contact linear switch triggers the nock to illuminate immediately when the string is released and can be quickly turned off with the newly integrated external switch, a true evolution in the world's most reliable lighted nock system. Super Strong Clear Polycarbonate Construction Waterproof And Shock Proof Red/Green Strobing Nocks Fits X, H, S, And GT Arrows Each Nock In This Package Weighs Approximately 25 Grains Delivers More Than 20 Hours Of Lithium-Powered Battery Life 2-Pack