"Dominion" seems to be the name generally used for that model in the US, but I don't know how technically correct that is. IIRC, Holland referred to it as the Grade 2.

BTW, it seems to be generally agreed that Holland did not make these themselves, but had them made for them in Birmingham. Some sources say they were from Webley & Scott. A guy I know who apprenticed in Brum in the '40s says they came from Pople & Bennett. They're good quality guns though.
-----------------------------------------------------------------------