NuFletch Ignitor Nocks Red Universal Fit 3 pk.. Design strengthens the arrow to withstand the punishment of high speed bows. Insert design provides extreme accuracy and precision nock fit. Specifications for NuFletch Ignitor Nocks: Manufacturer: NuFletch Quantity: 3 Package Contents: NuFletch Ignitor Nocks Shot activated fully indexable require no tools to turn off always light and are 100 percent waterproof. Each multi-pack provides precision inserts for GT S H and X diameter arrows. No adapters needed select and install the Swiss turned insert for your shaft place the LED battery light into the nock and press fit the self-centering nock for unmatched accuracy. LED battery light replacement takes seconds.