Bristol/Allen Round Head Screw UNC Button Buton UNC

The Bristol/Allen button round head screw is an industrial fastening element with Bristol or Allen drive, used in visible assemblies, housings, covers, and joints with lower head height. TECTUL offers it in carbon steel, UNC inch thread, and UNC thread reference when applicable to the product design. Selection must start from the thread, usable length, head type, and compatibility with the existing threaded part or nut. Compared with a countersunk Bristol screw, it does not require countersinking; compared with a cylindrical head, it offers a lower profile and cleaner finish. For this lot there are actual sizes such as 1/2 X 1 to 3/16 X 1/2, sold by unit. It is an option for maintenance, fabrication, equipment assembly, spare parts, and assemblies where precise, removable fastening with good tool access is required.

Available sizes

Installation recommendations

• Confirm whether the required thread is UNC, UNF, or metric before requesting a quote; do not mix pitches even if the diameter looks similar.
• Use a Bristol/Allen key in good condition and fully seated to avoid stripping the internal socket.
• Verify that the length does not bottom out in blind holes and that it allows proper seating of the head or tip.
• On stainless steel, avoid contamination with rusted tools and consider compatible lubrication to reduce galling.
• When the joint is critical, define the torque according to the drawing, base material, and project installation procedure.

We dispatch to Bogotá, Medellín, Cali, Barranquilla, and all of Colombia. Request a quote via WhatsApp for the Bristol/Allen button round head screw, indicating size, thread, material, quantity, and whether you need equivalence with DIN, ISO, or inch thread.