L9 Bar Mine Bar mine L9 is a large rectangular British anti - tank landmine . The bar mine ' s principal advantage is its long length - a typical anti - tank landmine is circular , and for it to activate a vehicle ' s wheel or track must actually press on the mine . The vehicle ' s wheels or tracks actually make up only a small proportion of its total width . To increase the probability of a vehicle striking the mine , the mine ' s effective trigger width must be increased . The bar mine allows a 50 % reduction in the number of mines in a minefield without reducing its effectiveness . It was reported that it would take 90 sappers 150 minutes to lay a 1 , 000 yard mine field consisting of 1 , 250 Mk 7 British anti - tank mines , weighing a total of 17 tonnes . By comparison , it would take 30 sappers 60 minutes to lay a 1 , 000 yard minefield consisting of 655 barmines weighing a total of 7 . 2 tonnes . The long mines can also be laid through a simple plough attached to the rear of a FV432 armoured personnel carrier . Laying circular mines in similar fashion requires a far larger plough and more powerful towing vehicle . The bar - mine laying FV432s were also usually fitted with launchers for the L10 Ranger Anti - Personnel Mine , to make subsequent clearing of the minefield by hand by enemy sappers more difficult ; however , the L10 has been withdrawn from service , in line with several conventions regulating mines which have been agreed to by the United Kingdom . The mine is made of plastic , and cannot be detected by metal detector s . A metal plate is attached to mines which are intended to be subsequently recovered by friendly forces , usually for training purposes . A full width attack mine ( FWAM ) fuse and an anti - disturbance fuse are available for Barmine ; these are secured on the ends of the mine , adjacent to the pressure plate . If either is used , the mine must be laid by hand . A training version of the mine is " bio - degradable " , and consists of sand or peat in a cardboard casing . Service . The mine entered British service in 1969 . A number of sub - variants of the mine exist , designated L9A1 through L9A8 . It is currently scheduled to be replaced in British service in 2010 . The L9 Bar Mine saw service " in anger " with small detachments of special forces of the British Army during the Gulf War of 1991 . A number were captured from Kuwaiti Army stocks by the Iraqi Army in 1990 , and subsequently used by them in the same conflict . It was reported that they disabled a number of M60 Patton tanks and other armoured vehicles belonging to the United States Marine Corps , even those fitted with mine - clearing ploughs . Unless the plough struck the mine squarely in the centre , the mine would often be rotated into a position in which it would blow up the track and front roller of the tank . The British Army has since been using bar mines simply as demolition charges , for instance to blow holes in tough compound walls in Afghanistan and Iraq . Among other users have been Denmark , where it was introduced as the " Pansermine M / 75 " , with the mine plough towed by the M - 113 APC . In 1989 an electromagnetic FWAM fuse replaced the original fuse as " Pansermine M / 88 " . Both mines have since been taken out of use .