Paul,
mostly 15A devicing here on 20A general lighting & receptacle circuits.
i see few 20A male cord caps, there was one that came with my PVC bender, which i replaced with a 15A.
Great circuit tester.....
but now that you've brought it up,i think the mega-hair dryers we have exceeds the male cord cap technically , some close to 1900W.
manufacturer's....they <ahem> rule here....
