The Nockturnal Launchpad Crossbow Nock is easy to install easy to use and specifically engineered to light up every shot with high-visibility LEDs. – BLACK COLLECT FITS: CARBON EXPRESS EASTON AND OTHER CARBON BOLTS SIZE WITH 0.284 INTERIOR DIAMETER – GREY COLLECT FITS: BEMAN BLACK EAGLE- BLOODSPORT GOLDTIP VICTORY AND OTHER CARBON BOLTS SIZE WITH 0.296 OR BIGGER INTERIOR DIAMETER – Features – 3 lighted nocks per pack – Each nock weighs approximately 30 grains – Comes with 2nd Grey Collet