<i>What does your catalog call these type of screw plugs?</i>
Bryant molded one-piece weatherproof plug:
Medium screw base. 4 1/2" No. 14 R.C. leads.
660 watts, 600 volts (!)
I've always wondered why American electricians use the term "cord cap" for what everyone else calls a plug, and I think I've figured it out. Way back when, this thingamajig was a plug. Then they came out with the two piece deals, one piece screwed into an edison-base lampholder (this was the plug base), and the other thing plugged into it, and that was called the cap.
This distinction was lost on the general public, to whom a plug was just a plug. Meanwhile, we are now several generations removed from the era when there were no wall receptacles, and thus "plug bases" are not thought of as being part of a two-piece kit.
Electricians still know to call a plug a "cord cap", but I bet most have no clue why.