1/4 x 2 1/2 Alloy Steel Socket Head Shoulder Screw (Stripper Bolt) with Nylon Insert provides a defined shoulder for controlled movement, accurate positioning, and serviceable fixture design. The important engineering feature is the shoulder, which supports positioning and movement while the threaded end retains the fastener. Typical applications include fixture plates, sliding elements, guide rails, and repeatable locating features. The nylon insert supports resistance to loosening while the shoulder continues to provide the bearing, guide, spacer, or locating surface. Machine builders can use the internal hex drive and shoulder geometry in compact assemblies that still require service access. The design is useful when the fastener is part of the positioning system rather than only a threaded clamping point. Common sourcing contexts include replacement maintenance, fixture construction, and OEM production support. Call Cold Headers at 773-775-7900 or email Sales@coldheaders.com for pricing, availability, or a quote.