A roll film negative. On board the submarine Sealion (1959) towards the end of a long refit at Portsmouth. The photographer is in the aft torpedo compartment between 108 and 117 stations on the main flat looking aft and to starboard from 112 station showing the torpedo order indicator Mk. 4 model 1 above a power supply panel on the left. An automatic emergency lantern and a telephone are next to the power supply panel. The closed door to the starboard torpedo tube (No. 7) is in the centre of the picture. A vertical format negative.