Starrett 52516 Reversible Combination Square Protractor Head

Product Description

The STARRETT 52516 is a reversible combination square protractor head designed for use with blades from 12 to 24 inches in length. Cast iron construction with a black smooth finish and chrome coating on the turret gives this head the durability required for layout, angle measurement, and scribing tasks on the job site or in the shop. The protractor head attaches to a standard combination square blade and allows the user to set and lock precise angles for repetitive marking or transfer work. It is a standard tool for machinists, millwrights, pipefitters, and tool-and-die tradespeople who require accurate angular layout.

This protractor head is suited for both shop and field use wherever combination square setups are needed for layout, inspection, or angle transfer. Compatible blade lengths range from 12 to 24 inches, making it adaptable to a range of workpiece sizes. It fits standard combination square blade configurations and is commonly used in metal fabrication, mechanical maintenance, and precision manufacturing environments where consistent angular reference is critical.

Key Features

• Reversible head design accommodates multiple blade orientations for flexible layout work
• Accepts blades from 12 to 24 inches in length
• Cast iron body provides rigidity and resistance to wear during repeated use
• Black smooth finish with chrome coating on turret for corrosion resistance
• Protractor head enables direct angle setting and transfer without a separate tool

Compatibility

Designed as an OEM-style replacement or upgrade protractor head for standard combination square systems accepting blades up to 24 inches in length.

Installation Notes

Installation requires sliding the protractor head onto a compatible combination square blade and tightening the locking mechanism per the blade manufacturer's guidance. No power tools or electrical shutoff are required for assembly. Inspect the blade groove and locking clamp for debris before mounting to ensure accurate seating and repeatable measurements.