This is a hydraption pack,which can use for outdoor sports,like running,cycling,hiking,camping,climbing and daily training. 1.The fabric is nylon ripstop with PU coating and light waterproof function. 2.Size is L26*H42cm 3.White logo on the front part,as well as reflective print logo on both sides for visibility and safety 4.elastic rope on the front part with snap hook can adjuste the space 5.front pockets with #5 zipper, 6.an opening pocket on the topy,you can put 1.0~2.0L bladder by velcro adjusted straps. 7. 2 pockets used spendex fabric on the padded shoulder straps for small things 8.2 small zipper pockets on wrist straps for small accessories. 9.mesh back for breathable 10.two sides can be used suitable for both left and right handers 11.metal zipper head with special zipper puller 12.reflective band on both of shoulder strap for visibility and safety 13.chest straps with buckles can be adjusted to make confortable 14.inside silk binding to be strong 15.handle straps for easy carry