Metallics TRM92M 10-32 x 3/4 in. Round Head Tri-Drive Machine Screws - Steel Zinc - Each

The TRM92M round head screw takes a slotted, Phillips, or square (Robertson) driver. The head is cut for all three, so whatever bit is already in your pouch will seat it. That is the point of a tri-drive on electrical work, where you are switching between device screws and box screws all day.

Yes. 10-32 is the standard machine screw thread used for grounding and device mounting in steel electrical boxes, and the TRM92M is a 10-32 thread at 3/4 inch length. The 3/4 inch length gives you room to pick up a tapped box ear or a grounding hole without bottoming out behind a shallow box.

It is steel with a zinc plating, which handles dry interior and lightly damp conditions. Zinc-plated steel is not a marine or chemically exposed fastener, so for wet exterior, coastal, or corrosive environments specify a stainless 10-32 machine screw instead.

Round head, as on the TRM92M, leaves a domed crown sitting proud of the surface, which is what you want in a tapped hole where there is no countersink and you need bearing surface against a strap or bracket. A flat head needs a countersunk hole to sit flush; a pan head has a lower, flatter profile where clearance behind a plate is tight. If the part you are fastening has a chamfered hole, round head is the wrong choice.

It is a 10-32 x 3/4 in. machine screw in zinc-plated steel, which matches the thread used for tapped grounding holes in steel boxes and enclosures. If your spec calls for an identifiable green grounding screw, that is a separate green-finished item, not this plain zinc one.

It is a machine screw, so it needs a pre-tapped 10-32 hole or a nut. It will not cut its own thread in sheet metal. For unthreaded sheet steel you want a self-drilling or sheet metal screw instead.

Yes, the TRM92M tri-drive machine screws are made in the USA. That matters on public and federally funded work where domestic-content language shows up in the spec.