The Nike HydraStrong is a highly durable material that provides long-lasting comfort and performance. The composition of this material is 53% polyester and 47% PBT. This fabric makes the swimsuit resistant to chlorine, sunlight and salt water. It is a very flexible material that will allow you maximum range of motion during wimming. The swimsuit is well breathable and quick-drying. These swimsuits are only partially lined with a thin layer of fabric in the front. The lining does not cover the entire front of the swimsuit. The swimwear have elasticated waistband for better tightening and comfortable wearing. The fastening string guarantees comfort. You can fasten the swimsuit by the string and you don't have to worry anymore that the swimsuit will fall down when you jump in the water.