Vlier PRTL250 Locking Knob Handle Plunger 1/4-20

Product Description

The VLIER PRTL250 is a locking knob handle plunger designed for precision positioning and retention applications in industrial and mechanical assemblies. The plunger features a Delrin knob and a steel body with a black finish, threaded at 1/4-20 for straightforward installation into standard tapped holes. It delivers an initial end force of 0.12 pounds and a final end force of 0.36 pounds, making it suitable for light-duty indexing, latching, and hold-down tasks. The body length measures 0.63 inches with a thread length of 0.50 inches. Licensed machine builders, toolmakers, and maintenance technicians are the typical installers of this hardware.

This plunger is used in production machinery, fixtures, jigs, tooling plates, and enclosure panels where a secure, manually operated locking point is needed. The locking knob style allows the operator to retract and lock the plunger in the retracted position, freeing both hands during part loading or adjustment. It is well suited for light-force indexing positions in both OEM equipment builds and field maintenance retrofits across manufacturing and industrial service environments.

Key Features

• Locking plunger type allows plunger to be held in retracted position during operation
• Delrin knob provides a comfortable, non-marring grip surface
• Steel construction with black finish for durability and corrosion resistance in shop environments
• 1/4-20 thread size fits standard tapped holes common in tooling and fixture work
• Compact body length of 0.63 inches suits tight clearance installations
• Low end-force range (0.12 to 0.36 pounds) designed for light-duty indexing and latching

Compatibility

Designed as an OEM-style replacement or direct-fit component for light-duty locking plunger applications using a 1/4-20 threaded hole in industrial fixtures, jigs, machinery panels, and tooling assemblies.

Installation Notes

Installation is performed by threading the PRTL250 directly into a 1/4-20 tapped hole using the hex size of 1/4 inch for torquing. Ensure the mating hole is clean and free of debris before installation. De-energize or lock out any associated machinery before servicing or replacing plunger hardware in active equipment. Do not exceed the rated end force range, as overloading the plunger mechanism can cause premature wear or failure of the locking element.