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 starboard, slightly forward and up from the main flat at 78 station. The battery vent trunk is on the right. A klaxon horn, an automatic emergency lantern, a vertical row of nine connector boxes and a tank capacity gauge are against the forward bulkhead. A vertical format negative.