What is this crazy sub ?

[Jimbuna]

There's a similar but newer version here:

http://www.diytrade.com/china/pd/109..._lifeboat.html

The one in the first post is almost identical to the one I trained on over twenty years ago, hence the condition due to age.

She is self-righting and designed to protect the occupants from fires as well as rough weather and some are designed to be lowered whilst others free-fall down a short ramp into the water.