Officially licensed by Mack trucks, these mini versions of the real things are bound to keep preschoolers busy for hours at a time. This rugged set includes an entire fleet of construction vehicles -- there is a dump truck, wheel loader and crane truck; plus two R/C construction workers and two transmitters. Each transmitter has 3 channels so more than one child can play at the same time. Requires 8 "AAA" batteries and 2 "9V" batteries, not included.