A roll film negative. On board the submarine Sealion (1959) towards the end of a long refit at Portsmouth. The photographer is in the bunk space between 49 and 52 stations on the starboard side of the main flat looking to starboard and slightly forward from 49½ station showing the two open vents in the battery intake trunk. The watertight door in 49 bulkhead is on the extreme left and a curtained fixed three tier bunk unit is on the right. A vertical format negative.