Our Solo backpacker sprayer has been a work horse for over 1 decade. They only item which needs changing is the shut-off valve. With time the compression spring wears out, and the item does not "shut off" the flow. Aside from that, Solo product is VERY dependable. We have 2 sprayers: one for herbicide and the other for pesticides. Just love them. We bought these shut-off valves as spares.
