Exped Dry bags are almost certainly the lightest drybag out there, well to the best of our knowledge. Great for keeping all your gear togther with-in other dry bags and whilst doubling up on dryness!

What they say :

100% Waterproof.  Designed to keep your gear dry.  Pack your clean gear to keep it dry or pack your dirty gear to contain the pong!  

Ultra lightweight see-through nylon ripstop fabric in bright colours. All seams are seam taped.