Our premium quality, fast-dissolving, granular shock chlorine. Packed in practical 400 gram bottles. 1 bottle treats 40,000 liters. Add to bucket of water to mix before pouring around pool edges. This product is best applied in the evening. Ideal for use when a strong chlorine shock is required; algae treatments, chlorine demand issues, superchlorination treatments. Can be used as a regular preventive shock.