AC Power cable for ARC Ref 5 se.

To expand on @cleeds response the key thing is what is the maximum current draw the cable will need to handle. If it’s >15A then you should really use both a 20A IEC and a 20A plug NEMA 5-20P (the sort in which the two flat prongs are at 90 degrees to one another vs the normal parallel).

This is why the Furman Elite 20 PFI ships with a cord with 20A IEC and 20A plug -- as the conditioner can supply, and can therefore draw, up to 20A.

ARC Amps on the other hand draw well under 15A (with the exception of the Ref750 which can draw 20A, wonder what sort of plug that ships with?) and while ARC uses 20A IEC sockets as (they believe) they give better contact and more secure connections then the traditional 15A its fine to use them with a cord with 20A IEC and traditional/normal 15A plug.

But in practice most manufacturers ignore the above and, especially in the case of power conditioners, simply ship them with a standard 15A type plug -- my Synergistic Research PowerCell 12 UEF SE being a case in point, rated to 20A but ships terminated 5-15P!

Finally to further complexify things in the current AQ Power Cord range the top of range Dragon comes in both a high current and low current version -- the former will support components drawing up to 20A while the latter (Dragon Source) is only for use with pre-amps and source components drawing lower currents (oddly AQ do not specify the current limit for the cable) -- they also argue the Dragon source sounds better on sources then the big, thich high current (and it costs half as much as well)

So all in all do take some care that you get the right set up for your needs 🧐

@d2girls most people wire their listening rooms with 20A receptacles but use 15A plugs in them 😉. The Furman was the first time I’d ever seen an audio component with a 20A plug

If you think about it the real reason for using a 20A plug is to prevent someone plugging something that draws 20A into a 15A standard receptacle and overloading the circuit. There's nothing in the design of a 15A plug that makes it unsafe carrying 20A provided the circuit its connected to is rated 20A. 

This is the reason the ARC Manual for the Ref750 (which as you recall will draw 20A) goes at lengths to stress the need to connect it to a 20A circuit ... it seems odd from a safety perspective that they don't simply supply 20A plugs as well ... maybe because Oyaide et al don't make audiophile grade 20A plugs?

folkfreak

... the real reason for using a 20A plug is to prevent someone plugging something that draws 20A into a 15A standard receptacle and overloading the circuit. There's nothing in the design of a 15A plug that makes it unsafe carrying 20A provided the circuit its connected to is rated 20A.

Absolutely agreed. My suggestion to use a cable with a 15A plug on one end and a 20A IEC connector on the other was only intended for components that draw less than 15A, such as ARC preamps. In practice, if that cable were used on a 15A line with a component that actually could demand 20A, the circuit's fuse or circuit breaker should trip. But it's bad practice to rely on a safety device in that fashion.