Mom won't let you have a tattoo on your arm? Maybe she'll let you have one on your cap! FLX fit: Introducing Speedo FLX Fit, the first silicone swim cap specifically designed for fitness swimmers. FLX Fit offers greater elasticity and more comfort than traditional performance caps. The softer silicone compound created for FLX Fit caps offers increased ease of stretch for everything a fitness swimmer needs. Plus, the Micro Grid Texture on the inside of the cap provides more comfort with less snagging and pulling of hair while keeping the cap in place. Latex free.