Due to shortage of Ericofons in the US, North Electric imported phones from Sweden or other markets. Those were then adapted to the specific US market needs.
To rebrand this dial face from Swedish to US type, a sticker on the outer part of the dial face has been applied to have the typical letters available.
More information on rebranding can be found in a previous post on these circles of mania.
Seems like this is also some kind of ‘official’ rebranding of the dial face. Never seen this one before but it looks quite professional. The picture I found somewhere on the web.