You never want something until you can't have it. So each week in The Sell-Out, we're getting the scoop from your favorite retailers on what's selling like crazy. Watch this space to find out what everyone's buying, sign up for wait lists, and keep tabs on restocks.When you find a carry-on bag that you love, you hang on to it and never let it go — even if the bag is completely falling apart and basically looking more like a beat-up, dirty piece of plastic than a piece of luggage. So, if you're long overdue for a new travel companion come 2017, consider this good-lookin' bag that's currently flying off of shelves. Designed by recently launched luxury travel brand Paravel , the Stowaway Suitcase in blue is almost sold out. The brand is down to single-digit quantities of the style, and it's anticipated that the bag will be entirely out of stock within the next week.What's so great about this suitcase, you ask? It's got quite the laundry list of perks, but what's most important to know is that the Stowaway collapses fully flat for super-easy storage, so no more taking up all the room in your coat closet with a few suitcases (that's valuable space, you know!). It's made of waterproof canvas and features best-in-class two-way, lockable zippers, a removable shoulder strap, and Italian leather binding for an almost vintage-looking but super functional vibe. And of course, it's properly sized for travel, so it'll fit comfortably in an overhead bin, and it retails for $275, a justifiable price point for a travel companion you'll have for a number of years.We can see why this fashion-meets-function travel essential is selling fast; if you don't manage to snag one now, our friends at Paravel tell us they're working on a restock soon. Click on to shop the Stowaway while it's still in stock, along with some other stylish carry-ons. Maybe it's time to consider finally retiring that scuffed-up neon hard-shell suitcase you got for graduation, okay?