A 35mm roll film negative. On board the Rothesay class type 12 frigate Rhyl (1959) in Devonport Dockyard. In the sonar instrument room on 3 deck between 12½ and 16 stations. The photographer is looking to starboard and aft from near the centreline of the room showing electrical cabinets with a servicing position against the starboard side of the ship and a cabinet marked SC No. 1 containing electrical first aid units on the right. The photograph was taken prior to 9 May 1972. A vertical format negative.