1. Intelligent tracking robot chassis with of freedom, suitable for DIY subjects, education, interest cultivation, children's educational toys and family education sets. 2. The mechanical structure is simple, and the universal wheels of the chassis are very flexible. It can move laterally without turning, adapting to difficult terrain. With these four new wheel combinations, full-sport functions are even more flexible and convenient. 3. No plug-in is very convenient, and the whole system is highly integrated. Can be used to measure distance and speed. Color: Yellow Material: plastic Product Description Application: STEM education, electronic projects RPM (with tires): 240 Tire diameter: 66mm Reduction ratio: 48:1 Current: 120mA Voltage: DC 6V Package Contents: 1 Assembled Electronic Auto Parts Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.