Chlorine resistant garments are made in a fabric to with stand the effects of regular use in chlorinated water such as fading and stretching. But of course the swimsuits can be used in any water. If you are undertaking aqua aerobics, hydrotherapy, swimming lessons or lap swimming. We highly recommend that you purchase a chlorine resistant swimsuit. Chlorine resistant garments will not contain any lycra or nylon elastane which is what perishes in heated pools and spas.