Highway Cheetah is a heavily customized suit that Silver Cross used to kidnap Fremea Seivelun and escape as quickly as possible from Accelerator. It is unknown whether Academy City intentionally built it for a purpose, or if it is a completely custom suit used exclusively by Silver Cross.
The Highway Cheetah is actually a powered suit inside another powered suit that was used to control the Edge Bees. It's appearance is armadillo-like with two arms and two legs, actually curl up into a ball. The Cheetah does not have any wheels but instead releases special oil and is moved by a giant propeller on its back thus sliding at speeds up 750 kph.
Silver Cross pointed out that the Dragon Rider and the Highway Cheetah had been constructed using the same technological concepts , meaning that the Cheetah internal computer could also feed the pilot with the necessary knowledge to pilot it.