Dual Size Set: Includes 180mm & 300mm extra-thick extruded aluminium rafter squares for versatile use. Its robust construction offers excellent resistance to rust, impact, and wear - ensuring long-lasting performance in demanding conditions. Featuring: Metric markings to the millimetre, conversion tables for rise and run application and extra-wide base for stability and secure holds on timber and straight edges. Easy to Read: Laser-etched markings provide excellent readability and twice the accuracy of stamped squares. Rapid Precision Marking: At 45° and 90° angles, exacting technical angles like rafter layout, or scribing notches at 5mm increments. Multi-functional: Capable of being a saw guide, scribing lines, pitching a roof, protracting purposes etc.