Pottery Barn Mackenzie Marvel's Spider-Man Glow-in-the-Dark Critter Backpack & Lunch Box BRAND NEW! Size: LARGE Gear them up for school, fields trips and everyday adventures with our glow-in-the-dark Mackenzie backpacks. Durable and well organized, they're made of water-resistant polyester crafted from plastic bottles with fun glow-in-the-dark details, and outfitted with pockets, straps and gear loops to keep everything in place. Adjustable padded shoulder straps ensure a comfy fit, while exterior straps and side pockets can hold a coordinating Mackenzie Lunch Bag and water bottle. Personalize your child’s backpack with their name or initials for a smart, extra-special touch.