On board the Royal Naval Reserve coastal minesweeper Mersey (1957) during the NATO exercise Northern Merger in the North Sea off the Danish coast. The photographer is on the port side of the sweep deck abreast the winch looking forward and to starboard showing crew members winding the cable off the Type B magnetic cable reel. The twin 20 mm oerlikon gun mount is abaft the funnel on which the number 10 is painted. The ship's name board is affixed to the gun deck guard rails. The rating in the foreground is a leading radio electrical mechanic.