Vlier M55N Threaded Spring Plunger 1/4-20 Steel Locking

Product Description

The VLIER M55N is a stubby threaded spring plunger designed for applications requiring high end force in restricted space. Featuring a 1/4-20 thread and a 0.531-inch thread length, this plunger delivers 1 pound of initial end force and 3.5 pounds of final end force. The plunger nose projects 0.078 inches and has a maximum diameter of 0.119 inches. Both the body and nose are constructed from steel, and the unit includes a locking element to secure the plunger in position once adjusted. Machinists, tool-and-die technicians, and mechanical assembly professionals install this component in precision fixtures and positioning equipment.

The M55N is suited for use in tight or space-constrained assemblies where a standard-length plunger will not fit. Its stubby profile makes it a practical choice for fixture plates, jig components, indexing mechanisms, and similar applications where accurate, repeatable positioning under load is required. The locking element makes it appropriate for installations where vibration or movement could otherwise shift the plunger setting.

Key Features

• Stubby plunger length type for use in restricted-space installations
• 1/4-20 thread with 0.531-inch thread length for standard tapped-hole installation
• 1 pound initial end force and 3.5 pounds final end force for high-force positioning
• Maximum plunger diameter of 0.119 inches with 0.078-inch projection
• Steel body and steel nose for durability in industrial and tooling environments
• Locking element included to maintain adjustment under vibration or load

Compatibility

Designed as an OEM-style replacement or direct-fit component for mechanical assemblies using a 1/4-20 threaded spring plunger in restricted-space, high-end-force applications.

Installation Notes

Install into a properly tapped 1/4-20 through-hole or blind hole using an appropriate hex key or spanner tool. De-energize or lock out any machinery before servicing components in moving assemblies. Do not overtighten, as this can damage the locking element or distort the thread. Confirm plunger projection and end force are appropriate for the load requirements of the application before final installation.