- Measuring head is attached to thegraduated steel rule (blade), allowing versatile measurements on various types of workpieces
- The measuring head comes hardened or cast iron-not-hardened
- Inside Spring Caliper - Ends fully rounded to give accurate contact with a workpiece.
- Square head: Used to set the rule at 90 degrees or 45 degrees to an edge of a workpiece.
- Center head: Used to locate centers of round workpieces
- Protractor head: Used to set the rule at a desired angle to an edge of a workpiece. Also used for measuring angles.