Starrett 56420 4-piece Combination Square Set 300mm

Product Description

The STARRETT 56420 is a 4-piece combination square set designed for precision layout and measurement work in trade and industrial settings. The set includes a hardened steel blade measuring 300mm in length with metric graduations at 0.5mm and 1mm intervals. Three interchangeable heads are included: a square head, a protractor head, and a center head, all constructed from forged steel and cast iron. Licensed machinists, pipefitters, sheet metal workers, and millwrights use combination square sets for scribing, checking squareness, measuring depth, and locating center points on round stock.

This set is suited for use in fabrication shops, mechanical rooms, and field installations where metric measurement is required. The 300mm blade length covers a wide range of layout tasks on both flat and cylindrical workpieces. The interchangeable head design allows a single blade to serve multiple measurement functions without additional tooling. Machinists and pipefitters working to metric tolerances will find the 0.5mm graduation useful for close-tolerance work.

Key Features

• 4-piece set includes square head, protractor head, and center head plus hardened steel blade
• 300mm hardened steel blade with 0.5mm and 1mm metric graduations
• Forged steel and cast iron head construction for rigidity and wear resistance
• Interchangeable heads mount to a single blade for versatile layout work
• Center head locates the center of round or square stock quickly
• Protractor head measures and transfers angles directly from the blade scale

Compatibility

Designed as an OEM-style combination square set suitable for general precision layout applications requiring metric graduation in fabrication, machining, and mechanical trade work.

Installation Notes

No power source or lockout is required for hand layout tools. Ensure the blade lock screw is tightened securely before scribing or marking to prevent blade movement during use. Periodically clean the blade groove on each head to remove debris that can affect blade seating and measurement accuracy. Store the set in its case when not in use to protect graduation markings and head mating surfaces.