Insulation ratings are confusing

[Pirate]

400 gram, 800 gram, 1200 gram. I don't know what any of that means, how do you figure out what insulation you need?

 

[Alan]

I just pick insulation based on whether my toes complained last season or not.

 

[Danny boy]

I used to be totally lost with those insulation numbers too. Then I realized they're basically just levels of warmth. I really just focus on wearing good socks and making sure my feet have enough room, rather than worrying about those numbers.