When temperatures are higher, you can detach the thermal liner that the waterproof Vertex H2O Jacket provides. The full TPU protector at the shoulders has the added advantage of being super flexible. Features polyester 600D detachable thermal liner hydratex® | G-liner SEESMART™ level 1 protection prepared for SEESOFT™ level 2 back protector insert - Type RV TPU protection at shoulder race fit, regular adjustment strap adjustment tabs VCS | zippers short connection zipper double front zipper jeans loop slit pockets inner pockets