Good quality: the straight ruler is made of high quality aluminum alloy materials, the corner frame is made of zinc alloy, never rust, not deform, thickness is 2mm , strong and durable for long-term use. High-precision workmanship: Adopt laser technology for high-precision workmanship, double-sided ruler in mm and cm graduations. Embossed graduation for easy reading and durability. Multifunctional: This combination square tool is practical and designed for drawing straight lines, drawing parallel lines, laying out, calibrating, measuring the bit depth of the router, set table saw blades. Multi-dimensional measurements: the carpentry square can achieve horizontal measurements, 90 angular measurements, 45 degree angular measurements, and can be used as a bevel at 45 degrees, height or depth measurer. With adjustable square head: Consists of a 300mm straight ruler and an adjustable square head for precise measurements. Helps you make precise angles and lines with the ruler and head.