Meets the performance requirements of Federal Specifications FF-T791b, Type 1, Form 1 - Class 6, and ASTM F-1145, except for those provisions required of the contractor.End fittings are Quenched and Tempered, bodies heat treated by normalizing.Hot Dip galvanized steel.Turnbuckle eyes are forged elongated, by design, to maximize easy attachment in system and minimize stress in the eye.For tunbuckle sizes 14" through 2-12", a shackle one and minimize stress in the eye.For tunbuckle sizes 14" through 2-12", a shackle oneTurnbuckle hooks are forged with a greater cross sectional area that results in a stronger hook with better fatigue properties.All products meet or exceed all requirements of ASME B30.26 including identification, ductility, design factor, proof load and temperature requirements.Importantly, products meet other critical performance requirements including fatigue life, impact properties and material traceability, not addressed by ASME B30.26.TURNBUCKLES RECOMMENDED FOR STRAIGHT OR IN-LINE PULL ONLY.Modified UNJ thread on end fittings for improved fatigue properties.Body has UNC threads.Fatigue Rated.