This robotic chassis kit contains of an acrylic base with two gear motors, two compatible wheels, a ball caster, and other accesories. Package Contains: 2 x Rubber wires 2 x Deceleration motors 2 x Aluminum fasteners 1 x Nylon all-direction wheel 1 x Chassis 1 x Battery box (4 x AA batteries, not included) 1 x Screwdriver