[High-tech material] Aluminum alloy square clamp. Made from a solid aluminum block, a durable material that will last for years. Surface treatment: black anodized finish. [Easy to use] Professional woodworking tools: Simply place the angle in the corner of the two parts you need at a right angle and secure it with an adjusting clamp. This set of brackets and clamps will make your work easier. [Wide application] These square mounting clamps with 90-degree positioning ensure a perfect angle and are widely used for assembly and DIY work on compression boxes, drawers, cabinets, frames, furniture cabinets, etc. [Size and packaging] Practical woodworking shows that this size set (140 mm squares) is a very scientific and correct choice.