Fit is IN, and version 2.0 of the super-popular, lightweight and body-mapped VaporAir race vest introduces the Adaptive-Fit™ adjustable sizing system. Long runs won’t ever be the same. See second image above for a comprehensive sizing chart! The Adaptive-Fit™ adjustable sizing system provides a tailored, body-mapped fit for all body types Breathable, chafe-free materials for maximum comfort Equipped with a 2L bladder with quick release valve Transparent zippered pocket for quick-viewing of key essentials Back kangaroo pocket for stashing flasks, layers, and other essentials Large main back storage compartment Front pockets fit bottles and flasks up to 22oz Reflective hits for 360-degree visibility Storage Capacity: 427 cu in/7 Liters Weight without Bladder: 8.3 oz/235 g Weight with Bladder: 12.2 oz/347 g