Use the metal hooks to securely attach the Accessory-Pack to the four points of attachment on the Handlebar-Pack. And if you don’t plan on spending the night outdoors and don’t need your Handlebar-Pack, you can still use your Accessory-Pack as a handlebar bag thanks to its pre-mounted Velcro straps. You can even use the carrying strap to transform the lightweight bag into a shoulder or hip bag.