At Amazon, get this Pelican Marine Water-Resistant Sling Bag for $19. It's the best deal Amazon has offered for this sling bag.
It's built with water-resistant, PVC-coated material and welded seams, plus a touchscreen-compatible window so you can use your phone without opening the bag. Buy Now at Amazon
Features 2-liter capacity sling bag IP64-rated water resistance with welded seams Touchscreen-compatible phone pocket fits most smartphones Splash-proof zipper closure with external loop system for attaching gear Adjustable, removable strap for crossbody or shoulder wear Measures 9.84" L x 5.31" W x 2.17" H and weighs 9.1 oz.