Pico is the smallest controller ACTion has ever produced. It should be run from 4.8 Volt (NiMH) to 6 Volt (Alkaline) batteries from where it gets the power for the motor - it plugs in like a servo). Ideal for small plastic kit models. Overall case size 34mm x 24.5mm x 16mm. Weight with case 16g. Can be left out of case for really tiny models, when weight is 9g.