Joy Walker Waterproof Backpack Rain Cover, 8000mm Waterproof Level, Upgraded Anti-Slip Cross Buckle Straps, Four Strengthened Layers for Hiking, Camping, Traveling For 30-40L backpack COVER HAS ELASTIC OPENING TO ACCOMODATE BAGS WITHIN THE FOLLOWING DIMENSIONS: LENGTH 9.8-13.7" WIDTH 5.9-9.8” HEIGHT 18.1-21.6" New, never used, excellent condition