4-40 x 1 1/4 316 Stainless Steel Button Head Socket Cap Screw is often chosen for equipment where the head style controls surface profile and the material supports wet or chemically exposed service. The button-head design gives engineers a compact rounded profile, a broad bearing surface, and internal hex drive access, while the 316 stainless steel material is selected where additional corrosion resistance is needed compared with general-purpose stainless grades.

Typical applications include commercial equipment and outdoor hardware, where 316 stainless steel is useful where humidity, weather, or cleaning exposure may be present. It can also serve packaging machinery and industrial automation, where reduced head projection helps limit interference near guards, rails, and moving components. The broad bearing surface and compact head profile make this style useful where covers, guards, or panels are handled during service.

For the 4-40 thread and 1 1/4 in. length, the reference head diameter is 0.201-0.213 in. and the head height is 0.051-0.059 in. The technical highlights below support fit checks for covers, guarded openings, and stainless replacement hardware.

Technical Highlights

• Material: 316 Stainless Steel
• Thread Size: 4-40
• Length: 1 1/4 in.
• Nominal Body Diameter: #4 (.112 in.)
• Head Diameter: 0.201-0.213 in.
• Head Height: 0.051-0.059 in.
• Hex-Key Size: 1/16 in.
• Drive Type: Internal Hex

Reference dimensions may vary slightly by manufacturer.

Call 773-775-7900 or email Sales@coldheaders.com for pricing, availability, or a quote.