Ventir is a modular backpack system that allows you to change the bag configuration to fit a range of carrying needs. Most people purchase one backpack for all their needs even though it is often bigger than necessary for daily use and too small for an overnight trip. Ventir is different. Ventir has a slim “Core” backpack onto which you can add one of three custom bags. Each module attaches with a zipper that runs around the perimeter of each unit. A wide “flap” allows you to easily harness the zipper. If you have a light day, simply use Core. If you need more stuff, zip on the “Basic” bag. The custom “Gym” and “Travel” bags can also be zipped on for gym visits or overnight trips. Each backpack combination looks completely integrated, and this design approach offers instant differentiation in a crowded market of lookalike and works-alike bags.