Inner Tubes - what model?

[mr_pacman]

I'm trying to understand what type of inner tube I need for a 2014 v7.  I see "type 1, type 2, type 3" and I also see "Type A, Type B, Type C etc". I suspect this has to do with the valve size and position?

I think the diameter I need is easier to figure out based on the tire size but does anyone know what the other specs are that I need to order?  All the websites I've seen have generic photos so it's not much help.

Thanks
James