These 4-Way Equal Pressure Clamp For Clamping Panels apply equal pressure from all 4 directions at once, from top, bottom, and both sides, saving the workpiece from accidental distortion. The clamp has plastic pressure pads so you don't damage the edge of your stock. Build any length clamp with the tough plastic bars with 12 notches for maximum adjustability to handle a variety of stocks widths. The clamp can be adjusted for boards up to 6" in thickness..