A roll film negative. On board the submarine Sealion (1959) towards the end of a long refit at Portsmouth. The photographer is in the generator room between 77 and 92 stations looking to port and aft from the main flat at 91 station showing the port and starboard pump starter units against the aft bulkhead at 92 station. A hand pump is on the left. Under the deckhead are boxes marked 'Shore supply to C.P. ring', 'M/g room comms transformer' and 'M/g room comms JB22'. A vertical format negative.