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 torpedo compartment looking to starboard and up from the centreline between 30 and 31 stations showing close detail of the framework on the upper and middle torpedo reload racks. Under the deckhead is a panel marked S.E.I.E. 4. Between the reload racks are units marked 'T.C.S.S. 9 socket for battery heating and monitoring' and they are labelled 'Stbd L.O.' Stbd M.O.' and Stbd U.O.'.