A roll film negative. On board the submarine Sealion (1959) towards the end of a long refit at Portsmouth. The photographer is in the motor room between 92 and 103 stations below the main flat looking forward and down to the bulkhead at 92 station from to port of the centreline at 95 station showing a 15 KVA 400 motor generator on the left above another motor generator. On the right is a 100 KW DC/AC motor generator. A steel box labelled L15 is on the deck against bulkhead 92. A vertical format negative.