 In the 1960s the Canadians developed a similar, but more reliable mine, the C3A1 ("Elsie") and the British army adopted it.The British also developed the L9 Bar Mine, a wide anti-tank mine with a rectangular shape, which covered more area, allowing a minefield to be laid four times as fast as previous mines.They also upgraded the Dingbat to the Ranger, a plastic mine that was fired from a truck-mounted discharger that could fire 72 mines at a time.