SB 2381 CSR Liquid is a liquid blend of organic and inorganic chemicals with a strong ammonia odor. It is de- signed to dissolve and lift the green stains that result from copper, bronze and brass corrosion. These stains are usually found on exterior concrete, unpolished marble and limestone surfaces. SB 2381 is the same as SB 2380 except it is not thickened. It may be used as a pretreatment cleaner and additive for SB 2382 CSR Poultice to remove the last of deeper set stains. Often the SB 2380 CSR Gel alone is