Simplicity 320 Skimmer: Collection Cup Drain Spout?

[bevo5]

Anybody know what tube size will fit the little drain plug spout on the collection cup? I can trial/error it but that adds up!

Thank you.

 

[bevo5]

1/2in!

 

[DentistReefer413]

1/2in!

This is 100% wrong! I ordered 1/2 inch based off of this reply and it does NOT fit! It's definitely metric, and a tad smaller. Just wanted to make sure if anyone reads this in the future - 1/2 inch slides right over the plug hose barb - find another conversion. I don't have the answer yet, but it's not 1/2 in.