Vlier PRT250 Non-locking Knob Handle Plunger 1/4-20

Product Description

The VLIER PRT250 is a non-locking knob handle spring plunger with a 1/4-20 thread and a Delrin knob, designed for indexing, positioning, and light-duty locating applications in mechanical assemblies. The plunger operates on spring tension with an initial end force of 0.12 pounds and a final end force of 0.36 pounds, making it suitable for applications requiring repeatable, low-force engagement. The maximum plunger diameter is 0.16 inches, and the body length is 0.63 inches. This part is typically installed by mechanical assemblers, tool-and-die technicians, or maintenance professionals working with jigs, fixtures, or light industrial equipment.

The PRT250 is suited for use in fixtures, jigs, tooling plates, and machine assemblies where a non-locking, hand-adjustable spring plunger is required. The Delrin knob allows for tool-free manual actuation, making it practical in applications where frequent repositioning or adjustment is expected. It threads into standard 1/4-20 tapped holes and fits in both light industrial and precision mechanical contexts.

Key Features

• Non-locking plunger type - allows free spring return without manual disengagement
• Delrin knob for tool-free manual actuation and comfortable hand operation
• 1/4-20 thread for installation into standard tapped holes
• Initial end force of 0.12 pounds, final end force of 0.36 pounds for light-duty positioning
• Compact 0.63-inch body length fits tight assemblies and shallow mounting locations
• Plunger projection of 0.13 inches with a maximum plunger diameter of 0.16 inches

Compatibility

Designed as an OEM-style replacement or direct-fit spring plunger for mechanical assemblies using standard 1/4-20 tapped mounting holes requiring a non-locking, knob-actuated plunger.

Installation Notes

Installation requires a standard 1/4-20 tapped hole of sufficient depth to accept the body length. Thread the plunger in by hand using the Delrin knob, then tighten to the desired seating depth using an appropriate wrench on the hex if needed. Ensure the mounting surface is clean and free of debris before installation. Do not overtighten, as this may damage the Delrin knob or distort the spring mechanism.