Vlier SPR375 Locking Pull Ring Plunger 3/8-16 Ss

Product Description

The VLIER SPR375 is a locking pull ring spring plunger designed for precise, repeatable positioning and retention in industrial assemblies. Threaded at 3/8-16 with a thread length of 1.2 inches, this plunger delivers an initial end force of 2 pounds and a final end force of 4 pounds. The locking pull ring mechanism allows the plunger to be retracted and held in the down position, preventing unintended engagement during loading or indexing operations. Machined from stainless steel, the SPR375 is suited for environments where corrosion resistance and mechanical durability are required. Maintenance technicians and precision assembly specialists install this type of component in jigs, fixtures, and automated equipment.

The SPR375 is used in positioning fixtures, tooling plates, indexing mechanisms, and assembly jigs across light manufacturing, precision machining, and industrial automation applications. Its locking pull ring feature makes it well suited for situations where the plunger must be held retracted while a workpiece is loaded, then released to engage a detent or registration hole. Both OEM equipment builders and MRO technicians specify this style of plunger for new builds and direct replacements in existing fixtures.

Key Features

• Locking pull ring retracts and holds the plunger out of engagement for hands-free part loading
• 3/8-16 thread provides standard fitment into tapped holes in steel and aluminum tooling plate
• Initial end force of 2 pounds, final end force of 4 pounds for consistent, controlled retention
• Plunger diameter of 0.233 inches with a projection of 0.375 inches for reliable detent engagement
• Stainless steel construction resists corrosion and wear in production environments
• Compact head height of 0.48 inches suits low-profile fixture designs

Compatibility

Designed as a direct-fit spring plunger for applications requiring a 3/8-16 threaded body with a locking pull ring and stainless steel construction.

Installation Notes

Installation requires a tapped 3/8-16 hole to the appropriate depth to accommodate the 1.2-inch thread length. Power down or de-energize any actuated or automated fixture before servicing spring plungers. Use a suitable wrench on the plunger head to achieve proper seating - do not over-torque, as stainless steel fasteners are susceptible to galling. Verify plunger projection and end force are compatible with the detent geometry before final assembly.