A simple condenser - with fan - is mounted where the chassis' rear fan would normally go. This connects to an expansion valve from where cooled liquid passes up to the CPU plate. The liquid moves on into a reduced-sized compressor before returning to the condenser to start the process again.
With copper running throughout the system, though, different configurations will be needed to suit differing motherboard layouts. And that appears to cause big problems for Thermaltake's plan to take this system into the mass market.