4-40 x 5/8 316 Stainless Steel Button Head Socket Cap Screw is used when the fastener head remains visible and the surrounding equipment benefits from 316 stainless steel construction. 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 instrumentation and control equipment, where the button head provides a finished appearance on visible panels and enclosure hardware. It can also serve machine building and maintenance repair, where the defined size helps match drawings, replacement hardware, and existing stainless assemblies. This style is chosen where the rounded head should remain visible, accessible, and smoother than many taller head forms.

For the 4-40 thread and 5/8 in. length, the reference head diameter is 0.201-0.213 in. and the head height is 0.051-0.059 in. The listed dimensions provide a concise reference for head clearance, tool selection, and part identification.

Technical Highlights

• Material: 316 Stainless Steel
• Thread Size: 4-40
• Length: 5/8 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.