Heavy-duty plate clamp is designed to vertically lift and turn plate material from all positions. Lifting clamp includes an articulating shackle for versatile, smooth operation and automatic serrated hardened steel pads and cams. Clamp features a safety mechanism that ensures the clamp does not slip when lifting force is applied or when load is lowered. Drop-forged carbon steel case offers maximum strength. Meets ASME B30.20 specifications. PERFECT FOR HEAVY PLATES: Able to vertically lift heavy duty plates that weigh up to 4400 lbs! EASY TO USE: Secure the clamp and move the plate material from any position, Jaw Opening up to 1″.