TenPoint Crossbows Universal Lighted Crossbow Arrow Nock System 2.0 (3 Pack) (HEA-368.3) PACKAGE INCLUDES translucent Omni-Nocks, LED Units, Nock Receivers (for arrows with shaft sizes .297, .300, .305 I.D), a Nock Receiver and Alignment tool, and a reflecting tool Fits MOST CROSSBOW BOLT SHAFTS on the market today Build your own lighted nock arrows! Nock Receiver glues into the nock-end of the arrow and must be indexed or aligned with the vanes Package of 3