'PK' was the designation of Allied convoys (together with a numerical suffix) plying the route from Pilottown, Mississippi to Key West, Florida, and as such reciprocals of the 'KP' series (September 1942/January 1943).

The series began with the PK.101 convoy of 8/11 September 1942 with the 5,228-ton US Chiloil, 4,710-ton US Henry M. Dawes, 1,068-ton Norwegian Idraet and 3,350-ton US Kewanee, and ended with the PK.135 convoy of 19/22 January 1943 with the 5,036-ton Panamanian Comol Cuba, 1,975-ton British Coteaudoc, 3,362-ton Honduran Gatun, 3,332-ton Honduran Granada, 4,548-ton US Henry D. Whiton, US King, 4,538-ton US Turrialba, 4,078-ton US Unaco, 6,901-ton US Vermont II, and 1,889-ton US commissioned cargo ship Pegasus.