Premium Material: Made of high quality polystyrene.This Material made this portable right angle corner ruler durability and Lightweight usability and economical. Easy to Use: Size: 6"/150mm, 4pc/set. Easy to handle. Place a square in the corner of the two stock pieces you need to square and secure with a set of clamps. Wide Application :Carpentry right angle jig set professional use to assemble and DIY by claping boxes, drawers, cabinets, frames, furniture cabinets, etc. Perfect for squaring up shelf cabinets. Maintain a perfect square while assembling frames, cabinets, or just about any box Professional Woodworking Tools:Designed to be clamped to boxes, picture frames, shelf cabinets and for outside corners.etc, to assist with squaring during glue up. It can work with clamping tool to check and position the corner for wood board jointing and gluing. It can be used for woodworking and welding at a right angle. Practical tool to make your woodworking project easier.