Easton 5mm FMJ 250 Spine Carbon Arrows - 6 Pack - More penetration, add kinetic punch for thick hide & bone with a full metal jacket. 5mm HIT 8-32 inserts included (16 grains) pre-installed 5mm X Nocks 5mm small diameter, High-strength carbon core with 7075-alloy metal jacket Easy target pull Straightness: ±.002in