The record for the smallest radio controlled car is a 25 mm long model (1/90 perfect scale) of a Mercedes Benz Smart car developed by Michihiro Hino, Tokyo, Japan in 2002. 

Specification: -RC equipment: 45MHz belt PSD system Toy-RC 2ch -Battery:Micro-nickel hydrogen rechargeable battery. -By continuation operation time: full charge,it is about 15 minutes.