End fittings are Quenched and Tempered or Normalized, bodies heat treated by normalizing. Hot Dip galvanized steel. TURNBUCKLES RECOMMENDED FOR STRAIGHT OR IN-LINE PULL ONLY. Forged jaw ends are fitted with bolts and nuts for 1/4” through 5/8”, and pins and cotters on 3/4” through 2-3/4” sizes. Modified UNJ thread on end fittings for improved fatigue properties. Body has UNC threads. Meets or exceeds all requirements of ASME B30.26 including identification, ductility, design factor, proof load and temperature requirements. Importantly, these turnbuckles meet other critical performance requirements including fatigue life, impact properties and material traceability, not addressed by ASME B30.26. Lock Nuts available for all sizes. Fatigue Rated.