We can guarantee that there will be no customs tax added for customers in the USA. For customers in Canada, the UK/EU and AUS, we have added pre-paid import duties into the shipping price.
For all other countries, after the shipment reaches your country it might be subject to import duties and taxes. Additional charges for customs clearance must be paid by you as we have no control over these charges and cannot predict what they might be.
Customs policies vary widely from country to country, please contact your local customs office for further information!