The product is gold-plated xuping - also called medical gold. Color change is minimized - durability is at a high level. It is a slip-on earring - it is worn from the thinnest part of the ear, paying attention to the ear folds. It is left where it naturally compresses, either downwards or upwards. You do not need to have a pierced ear to use it. It is sold individually. It does not affect pool and sea water. It should be protected from chemicals. Since it is in the hygienic product group, it is not suitable for exchange or return.