Hyper-Speed XT 100 is designed specifically for crossbows and ultra-fast compounds. Eleven rigid airfoils ensures the faster the Hyper-Speed XT is shot, the more spin-stabilization occurs. Patented Spiral Kut Tip makes the screw through the target, effect, producing the Spiral Wound Channel, most lethal wound in the archery industry. Rhino Tuff Xtreme blades .024" surgical stainless steel. 100 grain 1 1/4" diameter, 4 pack.