The Killer Instinct Hypr-V V-Track nock is engineered for superior accuracy in narrow axle-to-axle crossbows. Featuring the innovative V-Track design, it enhances nock-to-string contact, minimizes center serving wear, and is compatible with all Killer Instinct crossbows that use standard half-moon nocks. These nocks fit bolts with an inner diameter of .300" and come in a package of 12. V-Track design enhances nock-to-string contact Fit bolts with .003" inner diameter Press fit design Compatible with crossbows that use standard half-moon nocks Order today!