Hot Spring Watkins Freshwater 4-in-1 Shock Spas - 76755 Part Number: 76755 Hot Spring Balance Shock allows you to quickly shock your spa and re-enter in just fifteen minutes as long as the free chlorine does not exceed label recommendations. Watkins Freshwater 4-in-1 hot tub shock restores water sparkle in used hot tub and Jacuzzi water. No matter the model of your spa or hot tub, or when it was made - it's important that you regularly sanitize and treat your spa to prevent bacteria build-up. Choose from our selection of hot tub filters and maintenance products to find the right hot tub sanitizing system for your spa - at the right price! Hot Spring Spa Supplies carries spa fragrances, air & water valves, control systems, filter accessories, lights, cleaners, pumps, thermostats, and more for virtually every hot spring model.