This Tracer Speed Square offers quick and precise marking with 4 pre-calculated angle guides, allowing for simple 0°-90° marking by pivoting. It features horizontal and vertical rulers for quick measurements from the inside edge or T-section. The scales are clearly marked and won't wear off, including Metric and Hip + Valley rafter scales with 1/3 Rafter scribe guides for easy marking. Machined from robust yet lightweight aluminum, this square is designed for professionals and built to withstand the wear and tear of the worksite.