Make pool maintenance a breeze with HTH Pool Care Shock Ultra 1lb. This all-in-one shock treatment, formerly known as HTH Ultimate Shock Treatment, is your weekly chlorine superhero. Quickly boost chlorine levels, ward off bacteria and algae, and say goodbye to stains and scale. With its Cal Hypo formula, it not only keeps your water sparkling but also prevents chlorine lock, ensuring a hassle-free pool experience.