Warning - I tried to purchase some Uggs as a present and stumbled across the webstite www.ugg.gg who were offering a reasonable discount and worldwide shipping, having selected the items and proceeding to checkout my transaction failed twice after the additional Mastercard security and was then offer an alternative bank to try with the retailer which I duly declined to complete as I started to get a little suspicous.
To my surprise some 4 days later I noticed a transaction from www.agogomart.com on my crd statement and after some research linked this to the above trading site, I have found that;
(1) www.ugg.gg is one of many trading styles of a Chinese counterfeit trader
(2) That despite your card transaction being declined you will have inadvertently already paid
(3) That although Mastercard will not admit anything they are clearly aware of this trader and happy to help.