Salsa Saguaro Seat Bag – Dry Bag – 9L Medium. The EXP Series Saguaro Dry Bag is the center of our Saguaro Seat Bag system. Its removable from the Holster (sold separately) for easy packing or bringing your valuables with you at rest stops. Waterproof materials and construction keep contents dry and a purge valve lets you squeeze every last liter of capacity out of these bikepacking dry bags. Available in two sizes for all your adventures.