Easton Archery ST Axis Nano Shafts. The favorite choice for serious bowhunters looking for deep-penetrating big game performance. New Axis arrows are the first ever to utilize carbon nanotubes for increased strength compared to ordinary carbon arrows. Hidden Insert Technology aligns broadheads for tighter groups. Shaft Weight(Grains per Inch): 500(8.1), 400(9.0), 340(9.5), 300(10.7). Point and BAR sizes: 300's-9/32 BAR6, 340's-9/32 BAR5, 400's-17/64 BAR4, 500's-17/64 BAR3. Stock length 300's=32.5", 340's=32", 400's=31.5" and 500's=31". Comes with X-Nocks installed and H.I.T. inserts loose. Straightness: ¦ .003". Weight tolerance: ¦ 2 grains. High-strength nanotube infused carbon-composite fibers. X Nockùinstalled. HIT Insert, chamfer stone, installation tool, HIT epoxyùincluded when purchasing a full dozen. If purchasing less than a full dozen, only inserts and nocks will be included. Points and broadhead adapter ringsùsold separately. Shaft Weight(Grains per Inch): 500(8.1), 400(9.0), 340(9.5), 300(10.7).