The Handyhülle as such is fine. How can it be but that no statement is included here? When asked or request for issuance of such, which is not directly possible, unfortunately, only on Amazon, you get the answer that you should print out the order confirmation. Apparently white Smartphonez EN not that explicitly on the order confirmation is: "This is not a bill." A delivery note or here in particular an order confirmation is not an invoice and also meets the standards of the same not.. So for companies where accounting evidence required, not recommended. Who it as a private individual does not matter, you can order. It would just be interesting to see how the statutory right of return is regulated, when there is no proof of purchase / invoice no.