Why then still such a bad review? Because it is completely incomprehensible that you can get it absolutely no evidence when Amazon buys a voucher. So neither invoice nor receipt or anything else - not even on explicit demand from the customer service.
This is completely incomprehensible and very annoying when you want to take these coupons for example in relation to the tax office as income-related expenses.
So, good and simple product, but a thick hook is.