4-40 x 3/8 Cup Point 18-8 Stainless Steel Socket Set Screw with Nylon Insert gives a stainless, internal-hex set screw option for collars, hubs, and adjustments. One interface helps hold the collar or hub against movement; the other adds friction in the thread so vibration is less likely to loosen the screw. Use 18-8 stainless where the drawing calls for stainless material in indoor machinery, washdown-adjacent equipment, or humid service.

In packaging equipment, indexing stops, and machine adjustments, the internal hex drive allows adjustment from the end of the tapped hole. For torque-once settings without a pellet, compare 18-8 Socket Set Screws in the appropriate point style. This 18-8 family is not a heat-treated alloy-steel substitute; review the alloy version where seating torque is the priority.

Cold Headers brings long-running socket fastener knowledge to cup point set screw quoting and cross-checking. Review the thread size, length, hex key size, point style, and set-screw pellet location before matching the part to a service record or drawing.

Technical Highlights

• Point: Cup point, approx. 0.55-0.62 x nominal dia.
• Material: 18-8 Stainless Steel
• Thread Size: 4-40
• Length: 3/8 in.
• Drive: Internal Hex
• Hex Key Size: 0.050 in.
• Locking Feature: Nylon insert providing prevailing torque
• Nylon Insert Diameter (P): 1/16 in.
• Nylon Insert Location (N): 3/32 in. +/-1/2 pitch
• Dimensional Standard: ASME B18.3

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