5/16 100gr Glue on Field Points Archery Arrow Replacement Practice Tips 12pcs Glue on field tips for 8mm wooden arrows, bamboo arrows, fiberglass arrows ect. Inner Diameter: 8mm / 5/16 inch, Outer Diameter: 9mm, Lenght: 1.45 inch, Weight: 100 grain. Archery Broadheads Arrow Points 100 Grain for Target Practice. Arrow Components. 12pcs Archery Points per package.