1-8 x 4 is a case hardened low carbon steel square head set screw for machinery that uses wrench-driven adjustment or retention.

Typical applications include crusher and screen plants that use rugged retaining screws around shafts and collars. The five-point structure lets the same square-head size serve locating, bearing, and seating requirements. Half Dog points register into shallow holes or slots when location matters under load.

Cold Headers keeps the record focused on usable engineering details so buyers can compare the callout against drawings and service notes. Review the selected point, wrench clearance, and mating feature before substitution. External wrench access is useful when an internal socket recess would be hard to keep clear.

Technical Highlights

• Head: Square, wrench-driven
• Material: Low Carbon Steel, Case Hardened
• Point Styles: Half Dog, Full Dog, Cone, Oval, Flat (specify at order)
• Thread Size: 1-8 (UNC)
• Thread Fit: 2A (per ASME B18.6.2)
• Length: 4 in.
• Width Across Flats (F): 1.000 / 0.974 in. (max/min)
• Across Corners (G): 1.414 / 1.337 in. (max/min)
• Head Height (H): 0.774 / 0.726 in. (max/min)
• Dimensional Standard: ASME B18.6.2

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