If your parcel is being delivered outside the EU your parcel(s) will need to be acompanied by 4 copies of a customs declaration. It will need to be completed with full collection/delivery address, detailed list of contents with values . You will also need to add your VAT number or state not VAT registered if this is the case.
For deliveries to China you will require a CR number ( customs reference) which should be supplied by the receiver in China.