Thanks for the local context. All this stuff I picked up ages ago out of curiosity and a paper I did on the MPAA in college.
I seem to remember there being a lighter rating for kids, too - “Uc” or something, maybe?
There is an R18 rating in the UK - usually reserved for specially licenced sex shops and cinemas.
An E rating also exists for ‘exempt’ - usually sport, music and educational videos - though I can’t remember seeing one for a long time now; the E rating, not the R18, obviously 😃
Spend a lot of time in those sex shops, do you? 😉