Bohning Archery F Nock (.166" Shafts) - 12 PackBohning's F Nock fits micro shafts with an ID of . 166" (commonly known as 4mm or G Nock) shafts and G UNI Bushing systems. The F Nock features a double lock throat of . 120" (3. 05mm). Each F Nock weighs an average of 6. 5 grains (421. 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. NOT ALL BRANDS OF NOCKS ARE CREATED EQUAL At Bohning, every nock style must pass the