Carbon Express's D-Stroyer MX arrow shafts are constructed to incredibly tight tolerances, allowing them to retain more speed and accuracy when compared to traditional carbon arrows. They utilize Dual Spine technology, which places the weight of the arrow towards to front to produce tighter groups, twice the accuracy, and better penetration than arrows of a similar class. The rear 1/3 of the D-Stroyer MX features Diamond Weave, a patented technology that that provides ultimate stiffness 360 degree spine consistency. In addition, the D-Stroyer MX arrow shafts 2 Spine arrow shaft reduces oscillation by 50%.Features: Dual Spine Weight Forward - Patented 2 Spine arrow shaft that reduces oscillation by 50% vs single spine and has TWICE THE ACCURACYBuffTuff – Patented outer layer construction on the front 2/3 that provides a tough, silent carbon arrow finish plus makes it easier to remove from targets. Diamond Weave – Patented outer layer construction on the back 1/3 that provides ultimate stiffness and unparalleled spine technology. BullDog Nock Collars – Exclusive feature made of aircraft grade aluminum designed to prevent rear impact damage Laser Match Set – Pack sets are sorted & matched by spine and weight for best-in-class consistency. Spine sorting tolerance +/- .0025" & Weight sorting tolerance +/- 1.0 grains+/- .002 Real Straightness – Laser checked for straightness to remarkable 1/10,000 of an inchLaunchpad Precision Nocks – Controlled arrow release and integrated shaft alignment for more consistent accuracy. Q2i Rapt-X 2" Vanes Carbon Express D-Stroyer MX Hunter .400 Arrows 6pk 51147