The Swiss Tech 12" heavy duty machined square head. Offers 12" etched stainless steel blade with inch graduations, a full view acrylic vial, and a self- aligning draw bolt with a hardened scriber. Heavy-duty machined square head. It features permanent laser markings for superior readability in any light condition. 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 rafter layout 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. With this combined tool, you can measure if the painting is centered and paint a plumb line and so many useful features.