A roll film negative. On board the submarine Sealion (1959) towards the end of a long refit at Portsmouth. The photographer is in the control room between 59 and 69 stations looking forward, to starboard and down from 61 station showing the Mark 17 T.C.C. unit manufactured by Laurence Scott & Electromotors on the left with the Mark 1 torpedo order firing unit next to it. A junction panel and fuse boxes are on the forward bulkhead. An electrical power cable stowage container is on deck next to the battery compartment hatch. A vertical format negative.