Excalibur Diablo Illuminated 18in Carbon Crossbow Bolts - 3 Pack - Diablo Illuminated Carbon Arrows are specifically designed and spine for use in Excalibur's Matrix Series Crossbows and the speed they produce. 18in Arrow Length 263 grain Arrow weight .003in straightness tolerance 2in Blazer vane with a 3 degree offset Factory installed illuminated nocks by Lumenok Compatible with CeaseFire Technology crossbows and all models that utilize flat nocks.