Check the listing for details. 50Pcs Archery Arrows Nocks 4.2mm Insert Arrow Nock Replacement Orange. Condition: New. Listed at 16.99 USD. Archery nocks are small replacement parts attached to the end of the arrow shaft and play a crucial role in firmly connecting the arrow to the bowstring and helping the arrow fly. They are widely used in various archery sports, including archery, field archery, and bow hunting.SpecificationColor: OrangeMaterial: PlasticGroove Width: 2.5mm / 0.1 inchRod Length: 12.5mm / 0.49 inchDiameter: 4.2mm / 0.17 inchSize: 28.5x6.5 mm / 1.12x0.26 inch (L*W)Packing List: 50Pcs x Archery Arrow NocksAdvantageArrow nocks contribute to a smooth and consistent release from the bowstring. They minimize friction between the arrow and the string during the shot, allowing for optimal energy transfer and minimizing any interference with arrow flight.