what is that little picture that is pointing at lower unit oil seals ? ?

[vcreation]

so im looking to buy yammy parts and lower unit oil seals, however at the website there is a circle picture pointing @ the 2 oil seals.

what is that? does it mean anything special besides just push that oil seal in?

[99yam40]

It shows direction of the lip seal for both seals

[jmerrifield]

31 flat edge down, 18 flat edge toward the bow,raised toward stern

part 31 shows flat edge of the seal down, raised edge up.

[rodbolt17]

shows both lips(springs) face out.