IRWIN 2021418 18-Inch XP Clamp/Spreader This 18" XP Clamp/Spreader features a Power Lock System Applies up to 550 lbs of pressure Great for Cabinet Makers, Furniture Restorers, Fine Woodworkers, and General Construction Power Lock System Forward Pressure Trigger Die Cast Plate I-Beam Bar Applies up to 550lbs of Pressure