360 Digital Servo(EF90D) with wheel and tire is a kind of 360 deg analog servo. It is light and portable, a little bigger than 5 cent coin. It works at 3V voltage and uses pulse width to adjust speed of the servo rotation, which also can be used to make small robot modules, mechanical arm modules and intelligent car modules.
1 x EF90D micro:servo 360 degrees digital servo for micro:bit
1 x wheel