●Material:75% nylon,25% spandex,Light and close-fitting, comfortable and soft, light and breathable, sports hydrating, multi-dimensional fit to the body shape of the athlete.

●Size:S-M: 30.3-33.8in,M-L: 32.8- 36in,L-XL:40-45in,The manual measurement,error 1-2cm for the normal range.

●EXCELLENT FIT -- Elastic power-mesh materials are lightweight and completely chafe-free for comfort while running, shorter length delivers a close fit,Adjustable shoulder straps, sternum/chest and lumbar support, evenly distributed weights, comfortably wrapped around the body, unhindered.

●VERSATILE STORAGE - Gives you all the space you need to store your essentials. Whether it's an extra kettle, a phone or a key, different sizes of pockets are available for your storage needs. Energy replenishment warehouse, help forward.

●EXTENSIVE APPLICATIONS -- Our Ultra running backpack aims to accompany your trip of Running, Marathon, Jogging, Cycling, Backpacking, etc,Firmly shape the body without reducing too much volume and slowing down.