Dogline Viper Biothane Long Line 33 ft Lead with Brass HardwareThe leash is also available in 10 feet, 15 feet, and 20 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,