Metallics RM83B Screws 6-32 X 2 Rh Cd MS St-zn (Box 4000)

Yes, that is what the extra length is for. Receptacles and switches use 6-32 threads, so the RM83B threads into the same device ears and box tabs as a short device screw. The 2 inch length covers deep plaster rings, extension rings, and recessed boxes where the yoke sits well behind the mounting tab. On a flush box with no ring you would normally use a shorter 6-32, since the excess thread just projects into the box.

It is a machine screw, not a self-tapper. The 6-32 thread is a machine thread that needs a pre-tapped hole, a 6-32 nut, or the tapped mounting tab already in an electrical box or device ear. It will not cut its own thread in sheet metal or wood. For sheet metal without a tapped hole you need a self-drilling or sheet metal screw instead.

The RM83B is steel with a zinc plated finish. Zinc plating handles indoor and normally dry commercial interior work and gives light corrosion resistance, which is what the typical box and device application needs. For wet locations, exterior use, or corrosive environments, specify a stainless fastener instead rather than zinc plated steel.

They ship 4,000 per box, which is bulk packaging aimed at electrical contractors doing production device work or MRO stockrooms standardizing one mounting screw across a facility. If you need a handful for a single trim-out, this is far more than a service call quantity.

Round head. It sits on top of the surface with a domed profile rather than pulling down into a countersink, so it is not a flush fastener. Where the drawing calls for a flat head in a countersunk hole, a round head will stand proud and can interfere with a plate or cover sitting tight.

Order Metallics RM83B. That number covers the 6-32 x 2 inch round head, cadmium style zinc plated steel machine screw in the 4,000 count box, and it is the only model on the item, so there is no finish or length option to specify with it.