Electro Hardware THS3054M10F21 Steel Thumb Screw 1/4-20

Product Description

The ELECTRO HARDWARE THS3054M10F21 is a steel thumb screw with a knurled head, designed for tool-free fastening in light-duty mechanical assemblies. It features a 1/4-20 UNC thread pattern and measures 7/8 inch overall length, with a 1/2 inch head diameter and 1/4 inch head height. The knurled head provides finger grip for hand-tightening without a driver. Finished in zinc per ASTM B633, it offers basic corrosion resistance suitable for indoor and light industrial environments. This fastener is installed by HVAC technicians, electricians, plumbers, and general maintenance professionals wherever a removable, tool-free panel fastener is needed.

This thumb screw is used in applications requiring frequent access, such as electrical enclosure panels, equipment covers, junction boxes, and HVAC access doors. The 1/4-20 UNC thread is one of the most common fastener standards in North American trade work, making this screw a straightforward fit for repair and replacement scenarios across multiple trades. It is sold individually per package, with a minimum order of 2 units.

Key Features

• 1/4-20 UNC thread for broad compatibility with standard tapped holes
• Knurled head allows tool-free hand tightening and removal
• 7/8 inch overall length with a 5/8 inch thread length
• Zinc finish per ASTM B633 for corrosion resistance in indoor environments
• Grade 2 steel construction for reliable light-duty clamping force
• No shoulder design for direct thread engagement

Compatibility

Designed as a standard 1/4-20 UNC thumb screw for use in any application with a compatible tapped or threaded hole of that size. Suitable for use in equipment panels, enclosures, and access covers that accept 1/4-20 fasteners.

Installation Notes

Power down or de-energize any equipment before removing or replacing panel fasteners on electrical or HVAC enclosures. Hand-tighten only — do not use a driver or wrench on the knurled head, as this may damage the head or strip the thread. Verify thread engagement depth is sufficient for the panel thickness before finalizing installation. Follow applicable NEC or equipment manufacturer guidelines when fastening electrical enclosure covers.