The lead is also available in 15 feet, 20 feet, and 33 feet lengths. Our Biothane Working Lead is created from a high-quality Biothane waterproof coated webbing. A trusted name in national sports leagues as well as international military and space organizations, Biothane has a flexible substrate core that is bonded with a durable waterproof coating for protection. It is durable, cleanable, and has proven durability in applications where safety, cleanability, flexibility, and strength are crucial. Lead with purpose with the Viper Biothane Dog Leash This robust webbed dog lead is specially coated to emerge from even the swampiest environments, dry and smell-free, without loss of flexibility.