Equipped with the Alpha-Blaze Lighted Nock, the 20-inch, 410 grain lighted Pro Elite Select 400 features a precision spine-indexing manufacturing technique that increases accuracy by 33%, delivering tighter groups while maintaining the same point-of-impact as the standard Pro Elite 400 Carbon Arrows. Product Features The Alpha-Blaze provides bright illumination at the shot and the same point of impact as unlighted arrows. The Alpha-Blaze Lighted Nock contains a one-piece Nock/LED unit that is indexed with the vanes and press fits into the arrow s Aluminum Bushing. Upon firing the crossbow, the bowstring s force compresses the two pieces and activates the lighted nock. Deactivate the easy on/off Alpha-Blaze lighted nock by pulling the nock straight out until the light turns off no tools required. The LED light of the Alpha-Blaze system lasts for approximately twenty-four hours when activated. Weighing 410 grains, the precision spine-indexed Pro Elite 400 Select increases accuracy by 33%, delivering tighter groups while maintaining the same point-of-impact as the standard Pro Elite 400 Carbon Arrows. The arrow is equipped with the patented Alpha-Nock HP, which features a deep bowstring groove, a large smooth radius base, and elongated ears. The crossbow string wraps tightly around the center of the Alpha-Nock HP, resulting in straight nock travel and precision down-range accuracy, while minimizing serving wear. Each arrow is inspected for straightness to within .001 and each package is weight-grain matched within 1-grain per arrow. (The Alpha-Blaze can be used in any railed TenPoint, Wicked Ridge, or Horton Crossbow Innovations crossbow. Use of the Alpha-Blaze in any of these crossbows will not void the warranty, even if your crossbow originally required the use of a flat nock or Omni-Nock.) Product Specifications Nock Alpha-Blaze Lighted Nock Length 20" Weight 410-grains (+/- 1-grain) Straightness .001" Vane Q2i Fusion X-II 3.0 F.O.C 13% Insert Weight 58-grain Aluminum Insert Inside Diameter .300 Outside Diameter .346 Crossbow Compatibility Most TenPoint and Wicked Ridge Crossbows