Swim cap Nike Os Long Hair Silicone black NESSA198-001 The Nike swim cap will ensure a streamlined head shape, which will translate in to improvement of achievements . Flexible construction of hypoallergenic silicone recommended especially for people with long hair. Hair hidden under a cap does not impede swimming. The cap supports the protection of the hair skin against the harmful effects of chlorine and other agents added to water. Material: 100% silicone