Electro Hardware THS1003M07F16 Thumb Screw 4-40

Product Description

The ELECTRO HARDWARE THS1003M07F16 is a 303 stainless steel thumb screw with a knurled head and shoulder, designed for hand-tightening applications where tools are impractical or unwanted. It carries a 4-40 UNC thread and measures 0.6875 inches in overall length. The knurled head diameter is 0.375 inches with a head height of 0.1875 inches, giving a low-profile grip. The shoulder diameter is 0.312 inches with a shoulder length of 0.125 inches. Supplied uncoated, the 303 stainless steel construction resists corrosion in light-duty wet or chemically active environments. Electricians, panel builders, and mechanical technicians use these fasteners to secure covers, access panels, and instrumentation enclosures where frequent removal is required.

This thumb screw fits standard 4-40 UNC threaded inserts and tapped holes found across electrical enclosures, instrumentation panels, HVAC control boxes, and light mechanical assemblies. The with-shoulder design locates components accurately against a mating surface, making it a common choice in control panel fabrication and field-service applications where repeated hand removal is expected. The uncoated 303 stainless finish is appropriate for indoor environments and moderate-exposure installations.

Key Features

• 303 stainless steel body with uncoated finish for corrosion resistance in light-duty service
• 4-40 UNC thread standard for compatibility with common tapped holes and inserts
• Knurled head allows secure hand-tightening without tools
• With-shoulder design provides accurate component location against mating surfaces
• Compact 0.6875-inch overall length suits shallow panel and enclosure applications
• Meets multiple material and finish standards including ASTM B633 and QQ-S-763

Compatibility

Designed for use in any application with a standard 4-40 UNC tapped hole or threaded insert where a hand-adjustable, shoulder-style thumb screw is required.

Installation Notes

Installation requires no special tools — hand-tighten only to the torque appropriate for the mating material and application. Ensure the mating thread is clean and free of debris before installation to avoid galling, which 303 stainless steel can be susceptible to under high friction. Power down or de-energize any enclosure before removing or installing fasteners on live electrical panels, following applicable NEC requirements. Do not use power drivers on this fastener type.