The PileDriver Crossbolt is the heaviest carbon composite crossbolt in the Carbon Express lineup. Designed for the hunter who wants ultimate penetration, the PileDriver Crossbolt instills supreme confidence when tracking even the largest of prey. Bone-Crushing Penetration Heavy grain weight creates maximum kinetic energy and greater knock-down power Advanced Construction Ensures spine consistency for greater accuracy. Composite material is extremely durable at impact for exceptional reliability and repeat performance Real Straightness Precision sorted for straightness to +/- 0.004?, for repeat maximum consistency (maximum measurement, not an average 0.348" Diameter