Easton 9mm Brass Insert Flat Nock 22in Crossbow Bolt 6 pack - The Easton 9mm Bolt is built for strength and universal componentry. The 9mm Bolt has an inside diameter of 0.300" and will fit universal bolt components. High-strength carbon construction Inserts are included with fletched bolt Shaft weight: 8.9 gpi BTV Vane: 10 grains 9mm Crossbow Insert: 61 grains