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 auxiliary machinery and gland space (thrust block compartment) between 103 and 107 stations below the main flat. He is looking aft and to starboard showing the Johnson lathe in the foreground. Five lockers numbered 1 to 5 are against the aft bulkhead with a large air bottle above them.