Starrett 50128 Steel Square 1.5 in Blade and Base

Product Description

The STARRETT 50128 is a precision steel square designed for layout, inspection, and machining applications requiring accurate 90-degree reference. With a blade length of 1.5 inches and a base length of 1.5 inches, this compact square is built from high-quality tool steel for durability and dimensional stability. The 50128 delivers an accuracy of 0.0025 mm (0.0001 inches), making it suitable for precision work on the bench, at a vise, or during part inspection. It is a standard single-unit tool intended for machinists, toolmakers, metrology technicians, and precision trade professionals who require reliable squareness verification in a small form factor.

This square is suited for use in machine shops, tool rooms, and precision manufacturing environments. Its compact 1.5 inch by 1.5 inch geometry makes it well matched for checking squareness on small workpieces, setups, and fixtures where a larger square would be impractical. It is also useful in quality control and inspection workflows where space is limited and accuracy cannot be compromised.

Key Features

• Blade length: 1.5 inches; base length: 1.5 inches — compact form factor for tight work areas
• Accuracy of 0.0025 mm (0.0001 inches) for precision squareness verification
• Constructed from high-quality tool steel for wear resistance and long service life
• No bevel edge — straightforward reference square geometry
• Single-piece construction with no moving parts to wear out or go out of alignment

Compatibility

Designed as a general-purpose precision reference square suitable for bench use, fixture setup, and inspection tasks where a compact 1.5 inch steel square is required.

Installation Notes

No installation is required for this hand tool. Store the square protected from contact with abrasive surfaces to preserve its reference faces and maintain accuracy. Periodic cleaning of the reference surfaces and inspection for nicks or burrs is recommended to ensure continued measurement reliability. Handle with care to avoid dropping, as impact can affect the squareness of a precision ground tool.