Check your size
We have come up with what we hope is a rather ingenious way of checking what size Fin's shoe you are. Click on the link below to open a PDF document which has all the exact dimensions of the lasts of each shoe size. (The lasts are the mould-like contraptions put inside each shoe to give it it's shape and size - a sort of aluminium equivalent of your foot).
Print out this document and put it on the floor - a nice, hard floor would be best. Kick off your right shoe, and, if you think you'll be wearing your Fin's with bare feet, your sock as well. Place your foot on the outline of the sole, making sure that your heel matches the outline's heel as closely as possible. Now, this isn't completely foolproof, but you should be able to make out your Fin's shoe size!