Starrett 56399 12 Inch Combination Square Set 3 Piece

Product Description

The STARRETT 56399 is a 3-piece combination square set built for layout, inspection, and measurement work across a range of trade and fabrication applications. The set includes a 12-inch steel blade, a square head, and a center head, all machined to work together for accurate angular and linear measurement. The blade is graduated in 16R style, providing four graduation scales: 1/100, 1/32, 1/50, and 1/64 inch. The center head is forged steel for durability under regular shop use. This set is appropriate for machinists, pipefitters, millwrights, and other trade professionals who require reliable layout tools.

This combination square set is suited for both shop and field use where precise layout, 90-degree and 45-degree angle verification, and center-finding are required. The 12-inch blade length accommodates a broad range of workpiece sizes. The forged steel center head provides accurate bisecting of round stock or flat material. The square head allows checking of right angles and depth measurements. The 16R graduation style makes this set compatible with standard machinist and trade measurement workflows where multiple fractional and decimal scales are needed on a single blade.

Key Features

• 3-piece set includes a 12-inch steel blade, square head, and forged steel center head
• 16R graduation style with 1/32, 1/64, 1/100, and 1/50 inch scales on a single blade
• Forged steel center head for strength and dimensional accuracy under repeated use
• Steel blade construction for rigidity and resistance to wear
• Square head enables 90-degree and 45-degree angle measurement and depth gauging
• Center head allows accurate center-finding on round and flat stock

Compatibility

Designed as a standard-format combination square set for professional layout and inspection tasks in machining, pipefitting, millwright, and general fabrication trades.

Installation Notes

Combination square sets are hand tools that require no installation. Before use, verify that all head locking mechanisms are tight and that the blade seats fully in the head. Keep the blade and head surfaces clean and free of burrs to maintain measurement accuracy. Store in a protective case or tool roll to prevent damage to graduated surfaces.