Material and finish Made from an aluminum alloy for durability, with anodised surfaces for long life. Assembly and alignment features You have to assemble it by screwing the two pieces together. They have some clearance, which makes it possible to align them 100% when tightening the screws, for example by placing them on a flat surface. The millimetre scale and the 90 degree angle are accurate. Ease of use and measuring capability No assembly is required for operation: the milling cutter is easy to use and does not require any assembly. It can be used as a measuring tool and is very convenient for your use. Ruler design and compatibility Square ruler tools for carpenters: The ruler is a square design that fits most carpenter's sizes and shapes of workpieces. Practical use scenarios Use 1: When building frames, furniture, or cabinetry, to ensure precise 90degree joints and accurate measurements with the millimetre scale. Use 2: Onsite quick checks of alignment and squareness, using the 90 degree angle and the marked scale to verify cuts and placements. Use 3: As a general measuring tool during carpentry tasks, aiding alignment on flat surfaces before tightening screws or making final marks.