The Kwazar Neptune backpack sprayer has a 15-litre tank capacity and is used by spray operators across several industries. It comes with Viton seals (for maximum chemical compatibility), a pressure gauge, external safety valve and a telescopic lance that an operator could use to set the desired length to match his or her height. One advantage it that the sprayer can be pumped while still on your back, meaning there is no need to constantly remove and put it down.