A roll film negative. On board the submarine Sealion (1959) towards the end of a long refit at Portsmouth. The photographer is in the forward accommodation passage between 42 and 49 stations on the port side of the main flat looking aft from 47 station showing the closed watertight door in the bulkhead at 49 station. The fresh water vent and blow panel is on the right of the passage. Notices are against the bulkhead of the senior rates' mess on the left. A vertical format negative.