If you’re a bike commuter, you know how a sudden rainstorm can wreck your day. If your bike doesn’t have a rear fender, you can end up with mud, water, or road grease sprayed up the back of your clothing – not how you want to show up for a meeting or your work day. How would you like to be be able to quickly attach a fender when you need it, but not have to leave it on your bike at all times? How would you like to carry that fender with you on your keychain or in your gear bag? Musguard Rollable Bike Fenders are made from polypropylene plastic sheeting. They measure 41″ X 2″ and have a “special folding system for stability and a snug fit around the bicycle’s tubular frame”. When you don’t need it, you can roll the fender around the bike’s frame (shown in the top image), or roll it up and clip it to a keychain or stash it in your gear bag. The Musguard Rollable Bike Fender is available in orange or black for $30 at the MoMA Store. MoMA members get a 10% discount.