In order to avoid the gaps between the boards due to the tightening of the nut and the tightening of the top and the loosening of the bottom, we have developed the design of the top thin and bottom thick fixing block to achieve bonding of boards It'll be breezed to create the precisions 90 degree woodwork. Quickly and easily clamp on the squares Including 3-inch and 4-inch sizes, great for working with framed woodwork projects of different sizes Positioning squares featuring a high-impact ABS construction that insures durability and lightweight Such as cabinets or boxes, drawers, birdhouse, mailbox, picture frames and shelves. Holds square while glues is drying or fixing, Manufacturer: TOWARDSNAN