High penetration 5mm Axis SPT carbon arrows for shorter draw length and lower poundage bows. The 5mm micro diameter Axis SPT hunting arrows are compatible with all Axis accessory components. Includes X nocks and aluminum half out 8-32 inserts. Straightness: .006â?쳌. Available sizes: 500 (8.1 gpi.) 600 (7.2 gpi.) and 700 (6.1 gpi.).