We cover 1 year warranty by our side but NOT official warranty in customer's end while the detailed terms are the same as official warranty from manufacturer.
Customer first need to report the problem they have to us via email or eBay message system.
In case we require you to send us back the goods for exchange or repair, customer have to bear the sending back procedure and its cost while the final returning shipment from us to your side will be handled and covered by us.
Best check whether you have to send it back to Hong Kong if there is a problem with it. There is no mention of whether they are paying the import duty or VAT, so you'd be best clearing that one up a well.