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 to starboard from the centreline at 102 station showing the aft end of the starboard main motor on the left and the main motor cooler against the boat's side. Valves and pipework are against the aft bulkhead at 103 station on the right. A vertical format negative.