K Series three piece alloy steel rod end. Includes PTFE race lining. Female mounting with 7/16" bore and 7/16-20 left hand threads. Add a PTFE liner to the traditional three-piece carbon steel female rod end and you have QA1's KF-T Carbon Steel Series rod ends. Available in right and left hand threads and inch dimensions, these truly are precision rod ends. BALL 52100 Bearing Steel Heat Treated Hard Chrome Plated Precision Ground RACE Alloy Steel Corrosion and Wear Resistant PTFE Lined BODY Carbon Steel (Alloy Steel / Mfr./s Option) Protective Coated for Corrosion Resistance.