Horton's Lightning Strike MX Matched-Weight aluminum crossbow arrows feature 7075-T9 alloy for outstanding dependability and quality. Horton's Matched-Weight components optimize balance and accuracy, making this arrow the most consistently accurate aluminum crossbow arrow on the market. Available in vanes. Available in 3,6 and 72-packs. Length: 20". Weight (with 100-grain point) Vanes 432 grains. Straightness Tolerance: .003 at 20".