The Carbon Express D-Stroyer PileDriver is engineered for the hunter who wants ultimate penetration. Adding some weight to the line, the D-Stroyer PileDriver is the heaviest arrow in the Carbon Express line and designed to create maximum kinetic energy and deliver greater knock-down power. Dual Spine Weight Forward Technology - Patented 2-spine arrow shaft with heavier front for tighter groups and better penetration plus Reduces oscillation by 50% and twice the accuracy. PileDriver - Standard Diameter .244" ID for ultimate penetration and maximum kinetic energy. K-360 - Patented outer layer construction on the front 2/3 that integrates 100% high modulus carbon weave for consistent spine strength and durability. Laser Match Set - Pack sets are sorted and matched by spine and weight for best-in-class consistency. Spine sorting tolerance +/- .0025" and weight sorting tolerance +/- 1.0 grains. +/- .003 Real Straightness - Laser checked for straightness to remarkable 1/10000 of an inch. Launchpad Precision Nocks - Controlled arrow release and integrated shaft alignment for more consistent accuracy. Please Note: Color may vary.