Package includes 2x 12.75inch long notches , 2x 6.9inch long notches , 1x clamp assembly head, 1x clamp assembly tail, 16x assembly screws (4x 3/8inch, 12x 1-1/4inch L), and assembly instructions; 1 set with 1 clamp; Wood required, not included The 4-Way Pressure Release Clamp – Wood Panel Corner Clamping Woodworking Bracket Set handles stocking up to 6 inches (15.2cm) thick for simplifying the processes of countertops, furniture panel Stock stay flat and prevents buckling of board because of the equally apply pressure from all four directions More than lining up standard clamps and cauls; Attach notched to any length 1.5inchx1.75inch (3.2x4.4cm) board (equivalent to a 2x4 in half) with provided screws, set clamp and turn handle to tighten. Make sure the 2x4s you use not twist; Drill holes for the outer-most screws when attaching the pressure pad Build any length clamp with the with 12 notches for adjustability to handle a variety of stock widths; Turn the handle to tighten the clamp and unwinded the handle to release pressure; Clamp have pressure pad to damage of your stock, Manufacturer: XuQiZZpp