Patent 7128634 was granted and assigned to RadioShack on October, 2006 by the United States Patent and Trademark Office.
A radio-controlled car convertible from a two-wheel drive configuration to a four-wheel drive configuration is described. The radio-controlled car includes a chassis, a first drive assembly positioned in a first portion of the chassis, and a modular second drive assembly adapted to be inserted into a second portion of the chassis to modify the radio-controlled car to a four-wheel drive configuration.