LEGO Outdoor RC was a subtheme of Racers that consisted of four sets, the first set introduced in 2004 and the remainder sates were available in 2006. The theme contained RC LEGO cars that could be controlled by a wireless radio remote control unit. While the vehicles were compatible with TECHNIC, most of the pieces were proprietary to the specific models including the sets wheels.
2006 LEGO Sets
2006 for LEGO was a year of new themes being introduced and a number of well known themes being retired. LEGO in 2006 introduced and discontinued The Avatar: The Last Airbender, introduced the original Batman theme, Exo-Force, Mindstorms NXT, SpongeBob SquarePants, Remote control Trains and Aqua Raiders. However, the following themes were discontinued; Clikits, Vikings. While LEGO Sports was re-introduced in 2006 with a couple Soccer/Football sets.