Starrett 50130 Precision Steel Square 3 in Blade

Product Description

The STARRETT 50130 is a precision steel square designed for layout, inspection, and verification work in machining, fabrication, and tool-and-die applications. The square features a 3-inch blade length and a 2-3/8-inch base length, delivering an accuracy of 0.0001 inches (0.0025 mm). Constructed from high-quality tool steel, it holds its geometry under repeated shop-floor use. The bevel-free design keeps the reference edges clean and easy to use against workpiece surfaces. Machinists, toolmakers, and precision fabricators rely on this square for checking 90-degree angles, setting up vises, and aligning components on surface plates or mill tables.

The 50130 is suited for bench and machine-shop environments where close-tolerance squareness checks are required. Its compact size makes it practical for tight setups, scribing lines, and inspecting small parts. The tool is appropriate for both production and maintenance settings where accurate angular reference is critical. A single unit is packaged per order, making it easy to stock individually or as part of a precision layout kit.

Key Features

• Accuracy of 0.0001 inches (0.0025 mm) for close-tolerance inspection work
• 3-inch blade length and 2-3/8-inch base length in a compact, easy-to-handle form factor
• Made from high-quality tool steel for durability and long-term dimensional stability
• No bevel edge — clean reference surfaces for direct contact against workpieces
• Complies with California Proposition 65 standards

Compatibility

Designed as a general-purpose precision layout and inspection square suitable for machining, fabrication, and toolroom applications requiring 90-degree angular verification.

Installation Notes

This tool requires no installation. Handle with care to avoid dropping or impacting the reference edges, which can affect squareness accuracy. Clean the blade and base contact surfaces before use to prevent burrs or debris from introducing measurement error. Store in a protective case or designated tool location to maintain calibration over time.