Geosmina Small Seat saddle bag is entirely made of 600D Nylon and Hypalon. They also have seams, sealed using high-frequency welding technology. The 600D nylon is fully waterproof and has a PU (polyurethane) outer coating that repels water and makes the bag dry quickly when in contact with the air. The bags also have a TPU (thermoplastic polyurethane) coating which, together with the sealed seams, makes the bags completely waterproof. The saddlebags attach to the bike with two redesigned Velcro straps. Two large, Hypalon-reinforced Velcro straps attach to the seat post, and two more large Velcro straps attach to the saddle rails. These latter straps feature turnbuckles and heavy-duty YKK buckles that allow you to pull the bag tighter, so it always stays securely attached to your seatpost. The bags are closed via a roll-top closure which ensures a watertight seal and are further secured by YKK straps and buckles. The bags include an elastic band on the top that allows you to carry an extra load on the outside, as well as Hypalon reinforcements with reflective details to be able to install rear lights and thus improve rider safety. The bottom of the bags and the front panel (the one that rests on the seat post) is made of highly resistant and grippy panels of Hypalon. The bags are available in two sizes: Small with a 10 liter capacity and Large with a 15 liter capacity. The bag features the brand logos on a reflective material for better visibility.