They are usually powered by 1-3 batteries (depending on the model), similar to the size you would find in a car. They usually have a top speed of 8mph. Some even have wheelie bars for added safety.
They are meant for use on the pavement although you will occasionally see users driving them in the road and holding up traffic, oblivious to the queue of cars behind them beeping their horns in fury, and shouting.
Owners of granny wagons also tend to be terrible at driving them, especially around supermarkets. You will often see them rammed into innocent pedestrians and dogs at the hands of a novice.
Popular models include:
-Freerider Mayfair 4
-Pride Colt deluxe