Sonic Rush Nintendo DS 512k Prototype cartridge – SEGA UK press review item from approx 5 years ago. In perfect condition. Not sure if this is the final version of the game but I’m assuming it is. Writing on the front label reads… SO UK 512k. There is a sticker on the back (as you can see) and a Nintendo logo printed higher up the back of the cart. The cart unscrews to reveal the chip and dip switch inside.