Bohning's Blazer Nock fits standard carbon shafts with an ID of .246" (6.25mm, but commonly known as 6.5mm) and Super UNI Bushing systems. The Blazer Nock features a double-lock throat and a raised index. Its throat size is .120" (3.05mm) and each Blazer Nock weighs an average of 9.0 grains (583.2 mg). Tech tip: for easier insertion and indexing, apply a small amount of Bohning's Tex-Tite or Seal-Tite Wax to the nock shank