New improved Gardena nozzle for water rocket. The nozzle has a thread that fits into an ordinary plastic bottle. The improvement is that the nozzle is longer than the Gardena nozzle, which made i possible to design the inside of the nozzle so it's shape is reflecting to a real rocket nozzle. This means that the area of the waterbeam is much larger and resulting in at lager thrust. The thing is still under devolopment so please dont print before the final design is ready.