Hook – Hook Turnbuckles are rated with full thread engagement. Use caution to insure proper installation. “Rated Capacity” refers to a straight (zero degree) pull. Pulling at an angle can reduce the rated capacity significantly. Meets specification FF-T-791b, Type 1, Form 1 – Class 5. Open length estimated dependent on amount of full thread engagement at installation before take-up step. Design: Hook / Hook Material: 1045 Carbon Steel Process: Forged Finish: Hot Dipped Galvanized Threads: UNC Note: Smaller sizes may be electrogalvanized for better thread fit.