Secure-A-Tach Fastener is an easy-to-use loop fastener to permanently close them. These polypropylene fasteners reduce handling time with double-barreled locking head and an arrow tip that can be applied through either end of the barrel. They are easy to use. Simply insert the tail of the fastener into the head for a secure lock without tools or needles. Tensile strength is 12 lb. Perfect solution for tagging hard goods, they are fast, cost-effective and secure. Avery Dennison's proprietary stretching technology produces stronger, more flexible fasteners. Weatherproof loop fasteners are great for using on bags, luggage, sunglasses and other items where tagging guns cannot be used.