The hand held spray gun can hold about one litre of paint. This is a kilogram weight on the spray painters hand. The gun must also be refilled every few minutes. With every refill, you slow the job down and you stand a chance of a slight colour difference. By the time you refilled the gun, the previous paint has dried and the new paint forms marks and increases the polishing work. With the Airpower paint pressure pot, you can spray continuous until the 10 litre or 24 litre pot is empty. Without any delay.