Building off of the heritage of the Nano-XR™, the new Nano SST™ is an ultra-slim diameter shaft designed specifically for recurve bows. The Nano SST™ features Tri-Spine technology, with three specific spine areas with the stiffest being in the mid section of the shaft and the weakest spine configured to the back-end to allow for proper fletching clearance through the shot on a recurve bow. Nano SST™ has an ultra-slim parallel shaft profile that dramatically reduces cross-wind drift and is the ideal arrow for FITA, NAA and NFAA long-distance field shooting. Engineered for optimal velocity, strength and consistency, the Nano SST™ is constructed from 30-ton carbon so it will not take a set (permanent) bend and ensures faster recovery out of the bow and superior downrange accuracy shot after shot. - Advanced Technology, Extreme Accuracy. - Straightness: ± 0.002" - Weight tolerance: ± 1.0 grains - Spine selection tolerance: ± 0.002"