There is two versions. The sandwich version is the older but better quality version and is favored for some. The other but newer one is the same thing however much different design using a single pcb.
2 gpus and one pci-e switch (BR04) each gpu is in the 240 shader 448 bit configuration. They are both clocked lower than a GTX 285 but offer SLI on a stick (single brick or card).