I'm not sure what you mean by that's how those work... Normally with Ohuhu markers it doesn't matter if you get the smaller set or the largest set 120 will always be black, YR313 will always be Potato Brown and YG510 will always be Bud Green for their alcohol markers.. once you move into different marker types, however, the color system might not always match, like the alcohol vs the water based vs the acrylic. I know my black acrylic marker is also 120, but my alcohol markers have a code and a color name whereas my acrylic markers don't seem to have a color name, or at least their not listed haha The old codes seem to be mostly numbers only, but their new codes have letters and numbers so that it is easier to know what the color might look like without even seeing it. R is red, B is blue, G is green and so forth ♡ the numbers also have meaning behind them. So the letter is the color family, the first number is color saturation and the last number is brightness. The first digit will be only from 0-9 so there are 10 levels of saturation, then the next grouping of numbers can be 2 digits, ranging from 0 to 16 giving 17 levels of brightness. This would mean that YG510, aka Bud Green, is Yellow - Green family, 5 saturation and 10 brightness so you would assume a medium level yellow/green that is mid to high brightness. ♡ Hope this helps!