A roll film negative. On board the submarine Sealion (1959) towards the end of a long refit at Portsmouth. The photographer is in the auxiliary machinery space between 62 and 68 stations below the main flat looking to port, slightly forward and down showing the port side between 63 and 65 stations. On the right is a turbo blower manufactured by Keith Blackman Ltd and telemotor pump No. 2. A large air bottle is in the centre.