Metallics JCB42 Bolts 1/4-20 X 1/2 Carriage Blt St-zn (Jar 100)

The JCB42 is steel with a zinc finish, which handles indoor and dry damp conditions fine. Zinc plating is a sacrificial coating, not stainless, so in exterior exposure, washdown areas, coastal air, or anywhere with chemical or chloride contact it will eventually rust through. For those openings specify a stainless 18-8 or 316 carriage bolt in the same 1/4-20 size.

No. The JCB42 is not Buy American compliant and is not ARRA compliant, with country of origin listed as multiple. If your project carries domestic sourcing requirements, this part will not satisfy them and you need a domestically produced fastener.

The JCB42 ships as a jar of 100 bolts, and the jar is the order minimum, so 100 pieces is the smallest quantity. Other sizes and quantities are available by request.

A carriage bolt has a smooth domed mushroom head with a square neck underneath. The square neck bites into the material and keeps the bolt from spinning, so you tighten from the nut side only with one wrench, no screwdriver or second wrench on the head. The rounded head also leaves nothing sharp or snaggable on the exposed face, which is why it gets used on strap, hanger, and enclosure work. If you need to drive from the head side, or you need a higher strength structural fastener, use a hex head bolt instead.

The JCB42 is steel with 60,000 psi minimum tensile and 36,000 psi minimum yield, hardness Rockwell B70 to B100. Those are low carbon commercial fastener numbers, in line with general purpose carriage bolt stock, not a high strength structural grade. Use it for electrical, plumbing, and HVAC mounting work; for structural steel connections or anything carrying calculated load, specify a graded structural bolt instead.

No. The jar of 100 is bolts only. Order 1/4-20 nuts separately, plus flat washers if you want them under the nut, and lock washers or nylon insert nuts where vibration is a factor.