That's because the middle zipper on this sidewall provides convenient entry and access when you attach it to a 15 foot wall on any appropriately sized Caravan canopy. The sidewall attached easily to the legs and top of the shelter's frame, and there are even zippers along the vertical edges to make attaching to those separately purchase sidewalls quick and easy. You get a variety of color choices, all of the quality construction and safety compliance of other sidewalls and of the canopy top itself, and you get instant access into and out of your tent.
What you won't get is difficult setup, clunky operation, or a hefty price tag. This is an accessory that is easy to apply and easy to use. So, if you have an existing Caravan canopy with at least one 15 foot wall and you're thinking about adding some privacy or weather-resistance, this Caravan 15 ft. Middle Zipper Sidewall is an excellent choice.