Keeper 40 inch Ultra Bungee Cords combine technological advances with innovative features, making them stand out as the ideal bungee cord for a variety of personal and commercial needs. With a steel core inside, it is stronger than conventional bungee hooks and a glass-filled nylon outer sheath adds grip and protects belongings. All Ultra Bungee Cords are made from premium grade cord with a woven outer jacket that resists damage from UV rays and weather. Keeper bungee cords are available in a range of highly visible colors.