What if TS wants to buy his ring in SG, then come back to Msia? Will he kena custom tax since the item is so high value and heavy price tag?

Just wondering because when I came back from Aus to penang a few years ago, I had an australian bought ps3 which was already opened and used, yet still kena custom tax due to the value of the item (at the time about 400 AUD). So i am just curious