The Lezyne Ex Caddy is an expandable wedge shaped seatbag with a lower portion that unzips to offer even more storage. Features-Buckle system securely attaches the Caddy to the seatpost and seat rails-Durable, woven nylon fabrics, water resistant zippers, and reflective tail light loop for added durability and visibility-Labeled internal organizational pockets provide extra organization Item Specifications-Color:Black-Total Volume:49-Weight:115-Number of Compartments:2-Waterproof:No-Attachment Method:Straps-Primary Material:Nylon