Kathy from Canada writes
The Chapin 1 Gallon Pump Sprayer (#20000) does not have an on off switch. You will activate this sprayer by pumping up the air pressure until you feel resistance, then it has enough pressure built up in the tank so that you can begin spraying. When you feel the spray getting weaker, it is time to pump more air pressure into the tank. To release the air pressure you will simply lock the handle and turn it counterclockwise until you hear the air escaping. Here is the manual for this sprayer.
Answer last updated on: 03/22/2019