This a well designed, Arduino compatible mobile robot development platform,you can build it and program it easily with tons of published free codes. Compare with the last mobile platform, this one has a tough aluminium body with mounting holes, you can add Variety of sensors to make it more interesting.Features2WD Arduino compatible mobile robot development platform2 high-quality micro-speed motorTough aluminium body with mounting holesVariety of sensors can be addedSpecification2WD Mobile platform Motors: 3-6V DC Speed: 70cm/SDimensions: 170mm (diameter)Weight: 400gPackage listAluminium chassis X1wheels X2Motors X2Omni-directional Wheel x1Instruction Manual