7/8-9 x 3 3/4 is a UNC square head set screw for applications where the installed head can project and the point is chosen separately.

Typical applications include dirty work areas where an external square head remains serviceable when recesses collect debris. Half Dog, Full Dog, Cone, Oval, and Flat points are the ordering paths for this square-head series. External wrench access is useful when an internal socket recess would be hard to keep clear.

Cold Headers supports legacy square-head set screw requests where exact size and point selection matter more than generic substitution. Review the selected point, wrench clearance, and mating feature before substitution. Flat points bear against a machined flat without intentional penetration into the mating surface.

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: 7/8-9 (UNC)
• Thread Fit: 2A (per ASME B18.6.2)
• Length: 3 3/4 in.
• Width Across Flats (F): 0.875 / 0.852 in. (max/min)
• Across Corners (G): 1.237 / 1.170 in. (max/min)
• Head Height (H): 0.678 / 0.635 in. (max/min)
• Dimensional Standard: ASME B18.6.2

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