This is the UltrAspire MOMENTUM 2.0. Size: M This is a rare backpack that can store bottles on both sides of the waist. I am selling it to organize my gear. Please search online for more details. Thank you. The MOMENTUM is a trail running vest characterized by rear water bottle pockets located on both sides of the waist. This version 2.0 has been updated to be even more user-friendly. The new pockets feature a magnetic closure system that securely holds the bottles in place. To hydrate, simply pull out the bottle, and the magnetic hold is released, allowing you to quickly retrieve it. Magnets are also used on the pocket lid attached to the right side of the front harness. Small items such as keys, coins, and tickets can be quickly taken out and securely held to prevent them from falling out. I wore it once for a low-mountain hike. I am selling it because it didn't fit my body. Ultra marathon Trail running Trekking Mountaineering Hiking Clothing size: M