Vlier SLF250P Locking Knob Handle Plunger 1/4-20

Product Description

The VLIER SLF250P is a locking knob handle plunger designed for precision indexing, positioning, and spring-loaded retention applications in industrial and mechanical assemblies. Built from steel with a zinc gold chromate finish, this plunger features a 1/4-20 thread size with a 0.4 inch thread length and a knurled locking knob for secure, tool-free adjustment. It delivers an initial end force of 0.5 pounds and a final end force of 2 pounds, making it suitable for light-duty locking and locating tasks. The integrated locking element holds the plunger in the retracted position when needed, reducing interference during component loading and unloading. Licensed trades and machine builders working with jigs, fixtures, and assembly tooling rely on this style of plunger for repeatable, reliable positioning.

The SLF250P is suited for use in manufacturing fixtures, tool and die setups, and light mechanical assemblies where a compact, threaded spring plunger with a locking knob is required. The 1/4-20 thread makes it compatible with standard tapped holes in steel, aluminum, and similar materials. The knurled knob allows hand adjustment without additional tools, which suits frequent repositioning in production environments. This plunger is a direct fit for applications requiring a small-profile locking plunger with controlled end force and a defined plunger projection.

Key Features

• Locking plunger design holds plunger in retracted position for unobstructed part loading
• Knurled knob style for hand-tightening and tool-free adjustment
• 1/4-20 thread with 0.4 inch thread length for installation in standard tapped holes
• Initial end force of 0.5 pounds, final end force of 2 pounds for light-duty retention
• Steel construction with zinc gold chromate finish for corrosion resistance
• Compact head diameter of 0.5 inches and head height of 0.28 inches for tight clearance installations

Compatibility

Designed as an OEM-style replacement or new-installation locking knob handle plunger for industrial fixtures, jigs, and mechanical assemblies requiring a 1/4-20 threaded spring plunger with a locking element.

Installation Notes

Installation is performed by threading the SLF250P into a pre-tapped 1/4-20 hole by hand or with a wrench applied to the knob body. Ensure the mating thread depth accommodates the 0.4 inch thread length before installation. Disengage any stored spring force before removing the plunger from an assembly. Follow applicable machinery safety lockout procedures before servicing fixtures or tooling that incorporate this plunger.