What is "Smart Throttle"? Smart Throttle is a feature availalbe on some Aqua Joe hose nozzles that allows pressure to be adjusted with a simple slide of the thumb up or down. Related articles Is the water pressure adjustable? Aqua Joe CCPL50 Pool & Spa Calcium Hardness Increaser What material are the individual nozzles made of? My pressure washer is leaking from where the garden hose goes into the pressure washer.