Consists of an exceptionally strong plastic jacket with high frequency welded seams and a roll and clip top closure.   The bag in its rolled down closed state will accommodate a normal size mobile phone and electronic immobiliser.   A feature of this dry bag is that most phones may be used through the plastic.   A location point is provided at the opposite end of the roll top in order that the bag may be secured to a lanyard or into a kayaking jacket pocket.  The clip seals the bag thus making it airtight and waterproof.