 It was used by several Marine defense battalions, notably during Operation Cartwheel in 1943.The preferable prime mover was initially the Mack NO 6×6 7½ ton truck; from 1943 on it was supplemented by the tracked M4 High Speed Tractor.A small number of Long Tom guns were authorised for supply via lend lease channels, to the United Kingdom (184) and France (25).