Bulk Pack of 20 - As Low As $8.75 Per Kit! Teachers may need to supply additional materials such as foam, cardboard, etc. Includes: [20] Solar Cells (2V, 200mA) [20] Motors [80] Wheels [20] Gear Sets [20] Wood Bases [40] Axles Instructions PLEASE NOTE: KELVIN® reserves the right to substitute kit contents due to stocking availability issues.