On board the Type 12 frigate Lowestoft (1960) in No. 3 basin at Chatham Dockyard near the end of her modernisation which commenced 15 March 1968 and finished 31 May 1970. She was in the basin throughout May 1970. The photographer is in the engine room between 49 and 57 stations on 4 deck looking to port and aft from 53 station showing the port side air compressor fitted for the Agouti system. The Agouti system was a method of pumping high pressure air through holes in the edges of the propeller blades to reduce cavitation and noise. Six pressure gauges are in the foreground and two calorifiers are in the background. A vertical format negative.