Check the listing for details. Rx Clear Multi-Functional 4-in-1 Swimming Pool Shock 1 lb - (Choose Quantity). Condition: New. Listed at 20.92 USD. Rx Clear® Multi-Functional 4-in-1 Swimming Pool Shock 1 lb Bag - (Choose Quantity) Our Rx Clear® 99% Sodium Dichloro-s-Triazinetrione Dihydrate Multi-Functional 4-in-1 Shock is designed to dissolve quickly and completely providing a steady source of available chlorine in swimming pools to control the growth of algae, restoring clarity, kill bacteria, and destroying organic contaminants. Directions for Use: When the filter system is running and no one on the pool, broadcast 1 lb per 10,000 gallons of water directly into the deep end of the pool To prevent possible damage to pool surface, use a pool brush to disperse granules that may not have settled at the bottom of the pool Repeat after 24 hours, if needed, to establish a chlorine residual of 2 -4 ppm For bi-weekly shocking: with filtration system running add 1 lb. per 10,000 gallons of water directly into the deep end of the pool Features: MULTI-PURPOSE - Multi-Functional 4-in-1 Shock is designed to dissolve quickly and completely providing a steady source of available chlorine in swimming pools. Great for regular maintenance. NO MORE CLOUDY WATER - helps to control the growth of algae, kill bacteria, and destroy organic contaminants quickly. REDUCES CHLORINE ODOR AND EYE IRRITATION - Eliminate the smell of the harsh chemicals, and not irritating to your eyes or skin, but strong enough to zap bacteria away. DOSAGE - Recommended to use 1 lb per 10,000 Gallons about every two weeks TRUSTED POOL SUPPLIES - Rx Clear is your trusted, essential source for reliable spa and pool supplies, chemicals, and equipment. Count on Rx Clear to keep your pool clear and blue from opening day throughout the whole season