Enhanced Shock allows you to quickly shock your spa and also offers additional benefits like keeping the water sparkling and fresh. Enhanced 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. It also offers additional benefits¿like keeping the water sparkling and fresh. Restores water sparkle Removes unpleasant odors Multipurpose shock Can be used with chlorine or bromine spas and those using ozone/UV systems