This is an assembly kit of a 4WD model which appears to "walk" as the 4 wheels on its corners mover vertically, and climbs over obstacles up to 50mm with ease.

Wheel Walker assembly kit.
Kit includes everything needed for easy snap-fit/screw-together assembly. Simple wiring is required to complete the assembly. (No Soldering required)
Choose from 3 different chassis angle settings.
Requires one AA battery (sold separately).
May be combined with a 1.5V-500mA solar panel (sold separately; Item 76010).