Hi If you habve manage to escape from the sunken 500 Dollar propane tank
or oildrum made submarine and you are on the surface maybe some miles
away from shore - you need something to float dry - maybe a life-raft. 

Unfortunatly most life-rafts are expensive and didn't fit into a small
hatch of a one- or two-man submarine. 

The device on the picture is a 1,5m diameter childrens-play-pool for 
7 USD.. the smaller version with 1,2m diameter (4 feet) and about 6 UDS
cost fits even in the frontbag of the divers bouancy west !

All you need coustomize is a very small adapter to blow the unit
from the mouthpiece of the diver life west via the integrate pressure
air bottle. 

The helicopter crew even will like the nice red and yellow coulors.. 

You should have not to much metal work on your body or clothes - the
plastic skin of the pool is very thin.. 

Warning this file contains information which can safe your life.. or
kill you. Never use it for other porpose than it was designed for..
Keep at away from children.. it just a study.. 

regards Carsten