A roll film negative. On board the submarine Sealion (1959) towards the end of a long refit at Portsmouth. The photographer is in the motor room between 92 and 103 stations on the main flat looking to starboard at 95 and 96 stations from the walkway. On the left are a key cabinet next to locker L39. Above locker L39 is an A.L.K. drains unit with five inlets marked 'winch w/t box', 'cable cutter', handling equipment', tensioning pulley w/t box' and 'A.L.K. winch charging connection'. An automatic emergency lantern is mounted on the port main motor circuit breaker manufactured by The English Electric Co Ltd.