Chapin 1999 3.5-Gallon Pump-Free Compresssor Charged Industrial Sprayer For Industrial Strength Chemicals, 3.5 Gallon (1 Sprayer/Package) 3.5-Gallon Tri-Poxy tank for durability, pressure fitting for air supply 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) Brass wand, female brass fan nozzle and shut off with lock on feature. Poly holster keeps wand and nozzle secure Viton seals and gaskets designed to handle a variety of chemicals (check chemical manufacturers instructions) Unique Tri-Lock seal feature that locks the cap tight and pressure relief valve