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 aft, up and to starboard from 60 station showing the top of torpedo guidance control unit on the left with the conning tower hatch at the top. A conning tower isolating switch box, a signalling lantern resistance box, a conning tower lights fuse box, a klaxon horn and the klaxon horn push button are on the transverse frame abaft the conning tower hatch. The attack periscope is abaft the transverse frame.