1/4-20 Knurled Thumb Screws – A2 Stainless Steel + Aluminum Knob Bolts, Black & Red

Select a shaft length that allows full thread engagement in your tapped hole without the shaft bottoming out before the knob seats against the surface. For shallow panel mounts and camera tripod sockets, 6mm (≈1/4") to 15mm (≈19/32") typically works well. For thicker adapter blocks or stacked panels, 20mm (≈25/32") to 40mm (≈1-9/16") is generally more appropriate. For deep through-hole assemblies or long standoff applications, 50mm (≈1-31/32") or 60mm (≈2-3/8") may be needed. Measure your thread depth with a caliper before ordering to ensure a proper fit.

A2 stainless steel (304 SS) is a widely used austenitic stainless alloy with good tensile strength and excellent corrosion resistance. These thumb screws are typically suitable for light-to-medium clamping loads in camera rigs, instrument panels, enclosure assembly, and DIY fixtures. For heavy structural or high-vibration applications, contact us to confirm suitability before ordering in bulk.

The A2 stainless steel shaft offers good corrosion resistance and is generally suitable for outdoor and humid environments. The anodized aluminum knob body also resists surface oxidation well for most outdoor applications. For marine or salt-spray environments, A4 (316) stainless would generally be more appropriate — contact us if you need marine-grade options.

In most cases, yes. These use the 1/4"-20 UNC thread, which is the universal standard for camera tripod systems, quick-release plates, fluid pan heads, and optical bench hardware. They are generally compatible with Manfrotto, Joby, Arca-Swiss style systems, Benro, and most other brands that use the 1/4"-20 standard. Always verify the thread standard of your specific hardware before ordering, as some larger format systems use 3/8"-16 threads instead.

A standard hex bolt or socket head cap screw requires a wrench, hex key, or socket to tighten and loosen. These knurled thumb screws are designed to be tightened and loosened entirely by hand — the large knurled aluminum knob gives you enough grip surface to apply adequate torque without tools. This makes them ideal for applications where you need to frequently adjust, swap, or remove components in the field without carrying tools, such as camera cage panels, quick-release fixtures, and instrument covers.

Both colors are functionally identical — A2 stainless steel shaft with an anodized aluminum knob. Black blends with most camera and electronics equipment and is the most common choice for camera rigs and PC builds. Red is easy to spot in a gear bag or on a busy workbench and is popular for quick-release fixtures and color-coded assemblies. Many users order both colors to differentiate fasteners by size or function across a multi-component rig.

These use a 1/4"-20 UNC thread, which is larger than the #6-32 or M3 threads typically used in standard PC cases. In most cases, these are not a direct replacement for standard PC case thumb screws. However, they are well-suited for custom PC builds, open-frame rigs, and electronics enclosures that use 1/4"-20 threaded inserts or panel-mount hardware. Verify your enclosure's thread standard before ordering.