Of course, you can not only return your items purchased with us within 30 days (more details see cancellation policy, here), but you can also exchange it within the deadline. In this case, the goods may not have any traces of use.
If we have made a mistake and therefore you want to exchange, we of course take over the shipping costs. And their return costs to us (for proof, up to the amount of mailbox postal postage) and also the costs of new transfers to them.
If you want to exchange because you have mistaken, for example, we may ask you to take over the costs of new transfers (more details to the shipping costs, here).
In order for us to be able to assign your return quickly and safely, it is best if you put a copy of the bill in the package and clearly note what items we are allowed to take back.