Starrett 50373 Outside Spring Joint Caliper 12 Inch

Product Description

The STARRETT 50373 is a spring joint outside caliper designed for precise outside measurement in shop and field applications. Built with a 12-inch flat leg and a quick-nut screw adjustment, it allows machinists and toolmakers to take fast, repeatable measurements on round stock, shafts, castings, and similar workpieces. The spring joint maintains consistent tension during use, reducing the chance of slippage when transferring a measurement to a rule or micrometer. Constructed from polished steel, the 50373 is a traditional hand tool that remains a staple in machining, metalworking, and general fabrication setups where direct-reading instruments are not practical or necessary.

This caliper is suited for manual measurement tasks in machine shops, maintenance environments, and fabrication facilities. It handles outside dimensions up to 12 inches (300 mm), making it appropriate for measuring larger-diameter stock and components where a smaller caliper would not reach. Installers and machinists working with Starrett layout and measurement systems will find this tool integrates naturally into existing workflows. It is compatible for use with the Starrett 79 as noted by the manufacturer.

Key Features

• Spring joint design maintains tension and holds measurement position during transfer
• Quick-nut screw adjustment for fast leg-spread changes without losing spring tension
• Flat leg style provides stable contact on cylindrical and flat workpiece surfaces
• 12-inch leg length allows outside measurement up to 12 inches (300 mm)
• Polished steel construction resists corrosion and supports long service life in shop environments
• Includes adjustment screw as part of the standard assembly

Compatibility

Designed for use with the Starrett 79 per manufacturer specification. Suitable as an OEM-style replacement or supplemental tool for outside measurement tasks requiring a 12-inch spring joint caliper.

Installation Notes

This is a hand measurement tool and does not require power or mechanical installation. Inspect the spring joint and screw adjustment for smooth operation before use. Store with legs slightly open to avoid fatiguing the spring joint over time. Calibration against a known standard is recommended before critical measurement work.