The lightweight stretch woven material is durable and works with the body's natural movements;Ridged foam back panel for breathability and comfort;Two zipped security pockets to hold essentials;The left side opening features internal mesh pockets for easy gear organisation;The middle water bottle pocket centralises weight while riding;The right side opening features internal mesh pockets with compression phone sleeve and key fob;Fits most tubes including fat-bike and plus-sized models;100 cu. in. (1.364 l) capacity;