Metallics JHHN13SS Nuts 1/4-20 Hvy Hx Nut SS (Jar 100)

It's a 1/4-20 nut, so 20 threads per inch on a 1/4 inch coarse (UNC) bolt or rod. It will thread onto standard 1/4-20 machine bolts, hex cap screws, and 1/4-20 all-thread hanger rod.

They're 18-8 stainless, an austenitic grade, so they handle damp interiors, exterior strut and rod hanging, and washdown areas without the red rust you get from plain steel. Pair them with stainless bolts or rod; mixing stainless nuts onto zinc-plated steel bolts gives you dissimilar-metal corrosion at the joint.

A heavy hex is thicker and wider across the flats than a standard nut, so more threads carry the load and the bearing face spreads clamp force over a larger area. That's what you want on strut, pipe hangers, equipment anchors, and anywhere a standard nut would dig into soft or slotted material. The thickness here runs 0.218 to 0.250 inch with a 0.556 to 0.577 inch flats dimension. If you're working in tight clearance or the hole pattern is close-spaced, a standard hex nut is the better fit.

Metallics lists the JHHN13SS as both Buy American compliant and ARRA compliant, which is what public-works and federally funded specs usually call out for fasteners. Country of origin is listed as multiple, so confirm the origin marking on the jar you receive if your submittal requires it documented per shipment.

They ship 100 nuts in a jar, and the jar of 100 is the order minimum (counted by the each). The jar keeps loose small nuts out of the bottom of the gang box, which is the usual reason crews buy this format rather than a bulk bag.

Made to American Standard dimensions, so they interchange with other 1/4-20 heavy hex nuts already on the job and take the same 9/16 wrench. Hardness is Rockwell B95 to C32.