The Topeak Backloader X 15L is a spacious seat bag crafted for bikepackers who prefer a sleek way to transport their gear without a rear rack. Its reinforced, anti-slip and scratch-resistant fabric safeguards your saddle, while the advanced mounting system ensures a secure fit to the seatpost and saddle rails. The waterproof carry bag offers easy access, and the built-in air release purge valve keeps the bag compact and dry during your adventures. Key Features Material: Polyethylene, Anti-slip PU leather, Nylon, Engineering grade polymer. Lightweight, durable, water repellent, and stain resistant. Bag 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 / 20.1" x 9.4" x 8.7" (15 L). Weight: 525 g / 18.52 oz (15 L). With the Topeak Backloader X 15L, you can enjoy a hassle-free biking experience, knowing your gear is safely stored and protected from the elements.