Chapin Industrial Dripless Acid Staining Sprayer 2-Gallon No.22251XP. 2-Gallon Acid Staining sprayer with COPT Seals and dripless shut-off for the Decorative Concrete Professional. Now with 40% more pump volume per stroke. COPT seals and gaskets to handle Acid Based Concrete Stains. Translucent 2-Gallon poly tank. Pressure Relief valve. Dripless shut-off.