One of Big Skinny's most popular wallets, the perfectly balanced Slimline bi-fold wallet is designed with just enough unique slots to access your most frequently used cards in an ultra-thin package. It features a full-sized billfold area, four credit card pockets, an ID pocket with a clear plastic window for easy access to your driver's license or work badge and two oversized hidden storage pockets -- enough storage to keep more than 20 full-sized plastic cards. The extra-wide pockets are lined with a rubbery coating to prevent cards from slipping out. Designed with rounded corners for comfort, it's constructed of a lightweight, water resistant nylon microfiber material that is 5 to 7 times thinner and lighter than leather. It's machine washable for easy care and it dries out in about 20 minutes. The Slimline bi-fold wallet measures 4-1/2 x 3-3/8 Inch (and 4 mm thin when empty). The first Big Skinny wallet was designed by Kiril Stefan Alexandrov (the company's founder) because he loathed sitting on a thick, heavy leather wallet. Since creating the original Sport Wallet in 2005 using an advanced nylon micro-fiber material (5 to 7 times thinner than leather), Big Skinny has added dozens of slim wallet styles for men and women with more on the way.