Nathan Quickstart 4L Running Vest. One main compartment with a separate sleeve to put the bladder pack. Two additional pockets on the front straps - one that zip close (fits a phone) and one that cinches (good for snacks, gels, credit cards/id) Gently used, cleaned and ready for more use! Option to include a 1.5L bladder pack (cleaned) or to not include it. From the Nathan Website: > The essential QuickStart 2.0 3 Liter Hydration Pack with one main back storage pocket at back designed for the short to moderate road and trail running & hiking. > Moisture wicking stretch woven fabric & chafe free binding materials plus, breathable mesh shoulder straps. > Adjustable sternum straps.