A roll film negative. On board the submarine Sealion (1959) towards the end of a long refit at Portsmouth. The photographer is in the gyro compass room between 65 and 68 stations below the main flat, looking down towards the forward starboard corner. The gyro compass master unit is on a table on the left with two test sockets above it and an electrical unit and a CO² fire extinguisher below it. Cupboard three is in the corner and on the right are a Plessey Dynamics static converter Mk. 7VC and an Admiralty gyro compass repeater panel. A chair and a desk with a hinged top are in the foreground. A vertical format negative.