All Marine Grade 6061 Aluminum stock. Come with a trim ring for enhance appearance. Available in Black or Shiney Gun-smoke finish. Length 4.05" with a 0.512 bore. Two locknuts. Nut features Delrin washer for smooth nut-to-nut and nut-to-slide band operation. In addition to offering cork grips with inlet to accept the recess on the seat we also have a great selection of cork fighting butts.