Ultra compact seat bag is hidden under that saddle with hook and loop fastening strap to carry inner tube and tire levers for a safe and secure ride. Built-in anti-slip fabric provides mounting security. Three sizes and two colors available. RAIL WING SYSTEM Extra rail wing straps secure the Elementa SeatBag to saddle rails even while accessing contents MATERIAL 1000D Polyester water repellent and stain resistant / Aluminum ring MOUNT Saddle rails CAPACITY 0.2 L XS COMPATIBILITY XS - Up to 700 x 28c inner tube / 2 tire levers ATTACHMENT Hook and loop fastening strap Rail Wing System SIZE 10.5 x 7 x 2.7 cm / 4.1' x 2.8' x 1.1' XS WEIGHT 42 g / 1.48 oz XS