Electro Hardware THS3001M01F21 Brass Thumb Screw 4-40

Product Description

The ELECTRO HARDWARE THS3001M01F21 is a brass thumb screw designed for hand-tightened fastening applications where tools are not required or practical. It features a 4-40 UNC thread and a knurled head profile that allows secure finger-grip torque without a driver. The head measures 5/16 inches in diameter and 3/16 inches in height, with an overall length of 1/2 inch and a thread length of 5/16 inch. Constructed from brass with a zinc finish, this fastener is suited for light-duty assemblies in instrumentation panels, electronic enclosures, access covers, and similar hardware applications. Installation requires no special tooling.

This thumb screw is intended for use in assemblies requiring frequent manual removal and reinstallation, such as service panels, equipment covers, and enclosure doors. The 4-40 UNC thread is a common size in precision instrument and electronic hardware applications. The knurled head without shoulder design keeps the fastener profile low-clearance and straightforward to install into tapped holes or threaded inserts.

Key Features

• 4-40 UNC thread for compatibility with standard tapped holes in light instrument and electronic hardware
• Knurled head enables hand-tightening without tools
• Brass construction with zinc finish for corrosion resistance in typical indoor environments
• Without-shoulder design for a clean, low-profile installation
• 5/16 inch head diameter and 3/16 inch head height for compact fitment
• Meets multiple material and finish standards including ASTM B633

Compatibility

Designed as a standard 4-40 UNC knurled thumb screw for use in tapped holes or threaded inserts sized for 4-40 thread in instrumentation, electronic enclosures, and access panel assemblies.

Installation Notes

Installation is performed by hand into a pre-tapped 4-40 UNC hole or threaded insert. Ensure the mating thread is clean and free of debris before installation. Do not over-torque by hand, as brass fasteners in small thread sizes are susceptible to thread deformation under excessive force. No special tools or trade licenses are required for typical installation.