The Manson Reamers 12 Gauge Winchester/Remington Choke Tap comes with the threads TiCN coated. TiCN Coating, formally known as Titanium Carbo-Nitride coating, is an all-purpose strengthening coating that does especially well with cutting applications. Adding a total thickness of approximately .0001" - .0002" (2 - 5 Microns), TiCN coating will lengthen the life of your reamer and keep your tools sharper for longer. Screw-In Choke Tooling is only available as Removable (Live) Pilot Finishing Reamers. Pilot Bushings are not included. Additional Pilot Bushings can be purchased under Shotgun Pilot Bushings.The 12 Gauge Remington/Winchester Choke Tap has a 13/16"-32 H3 Thread that is optimal for Win Choke and/or Rem Choke applications. These tools come stock with a .625" shank that has .500" square flats.