Combination square

A combination square is a multi-purpose measuring and marking tool used in metalworking, woodworking, and stonemasonry. It is composed of a rule and one or more interchangeable heads that can be attached to the rule. The most common head is the standard head, which is used as a square for marking and testing 90° and 45° angles. The other common types of head are the protractor head, and the centre finder head.

Combination square

A combination square is a multi-purpose measuring and marking tool used in metalworking, woodworking, and stonemasonry. It is composed of a rule and one or more interchangeable heads that can be attached to the rule. The most common head is the standard head, which is used as a square for marking and testing 90° and 45° angles. The other common types of head are the protractor head, and the centre finder head.