Hi Laura,
The R4 is a little cartridge that allows you to play copy games on a Ninetendo DS. For about 2300 baht, you can buy one of these with a micro sd card that they will load up to 20 games of your choice on. You also get a web address where you can downlaod other games for free. These are available in Bangkok all over the MBK and they are a very good purchase. THe DS copy games are between 500-800 baht each so it makes the R4 pack a bargain. I am sure you will see them in Phuket, but I would tend to buy them at one of the shopping centres in Phuket town rather than off the street as they will need computer access to load your choice of games on to it. The new Jung Ceylon centre in Patong may sell them but I didn't see them when we were there in August.

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