We are happy to refund or exchange any goggles which are returned having been tried on at home. Of course, we can't refund or exchange once they've been worn in the water. You can usually see in a mirror how the seal is fitting, feel how comfortable they are and if they're leaving marks by trying them at home. Also, if we know what you've tried before and where the water is getting in, we might be able to suggest some suitable goggles to try.