The Big Daddy 2 Bike Rack Bag by BiKASE comes with a large expandable main compartment with a seam-sealed liner making the internal bag waterproof. Drop down panniers on each side, adding extra storage for when needed! MIK Mounting bracket included. Rain Cover included. Dimensions: 13" x 9" x 8" (with panniers). - Works only with MIK Rack - not Included