The EMPIRE?? True Blue?? Laser Etched 7 in. Rafter Square (e2994) has permanent laser markings for superior readability in any light condition. SCRIBE-GUIDEƒ?› precision scribe notches allow for easily marking parallel lines on lumber. Hi-visibility laser etched markings won't fade after heavy use. The rafter layout square is made from a durable anodized aluminum that is more durable than diecast and will not rust or corrode. The Empire rafter square has conversion tables for common applications. The square has an increased heel width that is up to 15% wider than leading competitors for increased stability on all job site material.