It seems like you're interested in silicone swim caps, potentially under the brand name Guardianwatersports. Silicone swim caps are a popular choice for swimmers because they provide a snug, comfortable fit while being durable and resistant to tearing. They are great for both casual swimmers and athletes, as silicone offers a smooth surface that reduces drag in the water. https://www.guardianwatersports.com/products/gobi-youth-swim-goggle-cap-set