The AMS Lava Crux? is the ultimate arrow shaft! It is an AMS engineered, patent pending, arrow shaft that provides more spine for a superior shot. The ultra-light Lava Crux? carbon core with fiberglass wrapped exterior ensures that the carbon cannot splinter or break! Due to the controlled manufacturing process, the weight and straightness of each shaft is very consistent with the next. Even with our stringent straightness specs on our arrows, the Lava Crux? surpasses all! We recommend these arrows for those shooting at higher draw weight and for those wanting to use the best available arrow shafts. Each shaft is manually inspected by AMS for straightness and is 5/16 in diameter and 32 long.