Oil breather pipe - diameter?

[-J-]

Anyone know what diameter pipe is needed for the breather from the back of the engine? I have 8mm in my head but not 100% sure.

Also any suggestions for a supplier for some Black Silicon hose ?

 

[-J-]

Sorted, no idea why I had the sizes above in my head, it's actually 14mm I'm told.

 

[len_beach]

18mm springs to my mind.

 

[-J-]

Hope it's not 18mm as I ordered the pipe now lol

 

[rich-6]

Was it 14mm? I take it thats the ID diameter?