Chapin 19149 3.5-Gallon Dripless Industrial Concrete Open Head Sprayer For Professional Concrete Applications (1 Sprayer/Package) 3.5-Gallon Tri-Poxy tank for durability and a 4-inch wide mouth opening for easy filling and cleaning Compatible for most professional concrete applications, suitable for homeowners too (check chemical manufacturers instructions) Professional dripless shut off with Comfort Grip lock on/off feature, brass wand and nozzle Viton seals and gaskets designed to handle a variety of chemicals (check chemical manufacturers instructions) Unique Tri-Lock seal feature that locks the pump cap tight