A roll film negative. On board the submarine Sealion (1959) towards the end of a long refit at Portsmouth. The photographer is in the sound room on the starboard side of the main flat between 56¼ and 59¼ stations looking to port showing the compartment sliding door. Above the door are a keel depth gauge, a type 197 sonar intercom mixer unit and a distribution fuse panel for Type 197 and type 719 sonars. Alongside the door are a fire extinguisher, an automatic emergency lantern, a sonar intercom switch box and a type 719 sonar intercom mixer unit. Against the forward bulkhead are 750v and 600v DC units. A vertical format negative.