A large capacity seat bag specifically designed for bikepackers wanting a streamlined way to carry gear without the need for a rear rack. The reinforced, anti-slip/scratch fabric protects the saddle while the advanced mounting system enables convenient and secure mounting to seatpost and saddle rails. Easy access waterproof carry bag and built-in air release purge valve keeps bag compact and dry while youre on your next adventure.Key Features:  Material: Polyethylene / Anti-slip PU leather / Nylon / Engineering grade polymer Lightweight, durable, water repellent and stain resistantBag attachment: Holster with hook and loop fastener and buckle fastener Waterproof rating: 10,000 mm (waterproof inner bag) Max load capacity: 5 kg / 11 lb Added features: Waterproof carry bag, Air release purge valve, Attachable rear light strap, Optional backloader Wishbone Size: 51 x 24 x 22 cm / 20.1x 9.4x 8.7(15 L), 46 x 24 x 22 cm / 18.1x 9.4x 8.7(10 L)  Weight: 525 g / 18.52 oz (15 L), 508