100% EVA Polyamide. Fastening: Quick Release Buckle. This swimming belt is buoyant and offers adjustable buoyancy, making it suitable for core strength training. Please note that the size guide image relates to standard sizes only; brand sizes may vary. Group images are not representative of the quantity sold; the pack quantity is listed separately. This product is usually dispatched within 3 working days. Delivery is typically completed in 3-5 working days within the UK mainland from the dispatch date.