Sometimes that doesn't work well with older receptacles. Usually I can solve that by squeezing the prongs a bit closer together.
[0] https://hackaday.com/wp-content/uploads/2018/04/dsc03649.jpg
Can't you put it into the upper socket, upside down? Most bricks do not have grounding, where the third pin would prevent that (or do they in NA?).
So it doesn't cover the bottom port with it's mass.
> if the end result is the same?
It is not; the difference is, that you could connect another brick to the bottom port.
But as Germans and their Schuko have shown, it doesn't really matter ;)
But, the ports thing is true - you have to put them in the bottom receptacle, and you can't have two of them in the same outlet.
This seems to be also local-specific; In Europe, the box contains both the extension cord and the "duckbill".
I consider replacing worn outlets to be just part of maintaining a house.
the tl;dw is "They're for manufacturing purposes" -- Alignment for when you're injection molding around them. Any other use is entirely secondary. NEMA sockets don't have any mechanism to hold onto the detent.
Under OSHA 1910.147(c)(5)(ii), lockout devices must be unique:
> Lockout devices and tagout devices shall be singularly identified; shall be the only devices(s) used for controlling energy; shall not be used for other purposes; and shall meet the following requirements:
Under OSHA 1910.147(c)(5)(ii)(C)(1), LOTO must be done such that a pair of bolt cutters alone would not simply bypass the lockout:
> Lockout devices. Lockout devices shall be substantial enough to prevent removal without the use of excessive force or unusual techniques, such as with the use of bolt cutters or other metal cutting tools.
McMaster-Carr offers only a single key-in-place LOTO for NEMA plugs, specifically 5-15 which clamps around the tines. This is a secondary use of the holes used for manufacturing but does not stop someone from giving a good solid tug, which can happen.
All other OSHA-compliant LOTO systems [encapsulate the full plug](https://www.mcmaster.com/loto-(lockout//electrical-plug-lock... or otherwise [bind to the body of the plug](http://lockoutmanufacturer.com/Pneumatic-Plug-Lockout3.html) in the case of circular connectors.
Note that OSHA LOTO rules do not stop someone from chopping the end off and putting a new connector on. They are intended to provide the broadest safety in the most common of situations.
FWIW I'd read c1 as stating that a lockout device need not be resistant to bolt cutters, as that would qualify as "excessive force or unusual techniques".
Some interesting discussion on this topic here: https://electronics.stackexchange.com/questions/11495/nema-5...
(Maybe I'm sensitive since I was literally shocked after just a couple of days working in a US office, simply connecting a charger under my desk when it sort of bent half way out. I was really surprised how simple it was to get exposed during normal use.)