This product is manufactured in our own workshop from modern materials for strength and salt water tolerance. Consist of a nylon and 316 stainless steel rust free swivel snap hook for a secure attachment. 25mm black nylon webbing with our label on and 4mm nylon cord all stitched with industrial nylon thread. The waterproof safety whistle (No Pee, No Jams) is bright orange and ideal for all watersports including Scuba diving. Also an excellent whistle for walking, hiking etc. Extremely loud and easy to blow when cold/wet and capable of producing over 100 decibels of sound. This quality nexus whistle meets the new safety standard ISO 12402-8. Please check out our other whistles we have a good selection.