[Technologies: ErgoFitTM MaxO2 SystemTM UltrAcool SystemTM Sizing Range: Universal. One size fits most. Total Volume: 214 c.i. (3.5 L). 4-way stretch mesh designed to expand or compress to the load and is built to carry a 1 liter reservoir. NOT INCLUDED Max 02 sternum for unrestricted breathing while maintaining a stable pack. Uses shock cord with good stretch for unrestricted breathing but also good rebound on the stretch for a stable ride. Magnon pocket for sweat-free pills. With automatic magnetic closure for rapid access to pills and other essentials. Weight: 7.5 oz (213 g)]