The Empire True Blue Laser Etched 12 in. Aluminum Rafter Square features permanent laser markings for superior readability in any light condition. SCRIBE-GUIDE precision scribe notches allow users to easily mark parallel lines on lumber. Hi-visibility laser etched markings won't fade after heavy use on multiple job sites. The Aluminum Rafter Square is made from a durable anodized aluminum that is more durable than diecast and will not rust or corrode after exposure to the harsh job site elements. The Empire rafter square features conversion tables for common applications. The Aluminum Rafter Square features an increased heel width that is up to 15% wider than leading competitors giving users increased stability on all job site material.