Alpinestars T Core Air Drystar Jacket - Black/BlackAlpinestars T Core Air Drystar Jacket Hot weather precipitation takes special consideration since a waterproof membrane will block both water and air flow. Alpinestars addresses this conundrum by stowing the detachable Drystar waterproof liner in a low profile pocket on the back of the jacket so you can run the mesh jacket right up until it starts raining and you attach the liner. The Alpinestars T Core Drystar Jacket vents to the waterproof liner