The M1, M1A1 and M4 are circular steel cased United States anti-tank blast mines with a distinctive cross shaped pressure spider. The mine was used during the

Second World War World War II or the Second World War, often abbreviated as WWII or WW2, was a world war that lasted from 1939 to 1945. It involved the vast majority of the world's countries—including all of the great powers—forming two opposin ...

and a copy produced in Argentina was used during the

Falklands War The Falklands War ( es, link=no, Guerra de las Malvinas) was a ten-week undeclared war between Argentina and the United Kingdom in 1982 over two British dependent territories in the South Atlantic: the Falkland Islands and its territorial de ...

. Another copy is produced in China. designated the No. 4 mine. Variants of the mine have also been deployed in

Chad Chad (; ar, تشاد , ; french: Tchad, ), officially the Republic of Chad, '; ) is a landlocked country at the crossroads of North and Central Africa. It is bordered by Libya to the north, Sudan to the east, the Central African Republic ...

and

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. Downward pressure on the spider presses down on the head of the

fuze In military munitions, a fuze (sometimes fuse) is the part of the device that initiates function. In some applications, such as torpedoes, a fuze may be identified by function as the exploder. The relative complexity of even the earliest fuze d ...

, breaks a shear pin, and inverts a

belleville spring A Belleville washer, also known as a coned-disc spring, conical spring washer, disc spring, Belleville spring or cupped spring washer, is a conical shell which can be loaded along its axis either statically or dynamically. A Belleville washer is ...

, flipping the striker downwards into a stab sensitive

detonator A detonator, frequently a blasting cap, is a device used to trigger an explosive device. Detonators can be chemically, mechanically, or electrically initiated, the last two being the most common. The commercial use of explosives uses electri ...

, triggering the mine. The M4 version of the mine has two secondary fuze wells so that

anti-handling device An anti-handling device is an attachment to or an integral part of a landmine or other munition such as some fuze types found in general-purpose air-dropped bombs, cluster bombs and sea mines. It is designed to prevent tampering or disabling, o ...

s can be fitted.

Variants

* M1 – the mine has two filler plugs on the top surface. * M1A1 – the mine has a single filler plug on the top surface. * M4 – as the M1A1 but with two secondary fuze wells, one on the side and one in the bottom.

Specifications

*Weight: 4.80 kg *Explosive content: 2.70 kg of

TNT Trinitrotoluene (), more commonly known as TNT, more specifically 2,4,6-trinitrotoluene, and by its preferred IUPAC name 2-methyl-1,3,5-trinitrobenzene, is a chemical compound with the formula C6H2(NO2)3CH3. TNT is occasionally used as a reagen ...

*Height: 102 mm *Diameter: 203 mm *Operating pressure: 120 kg to 250 kg

References

Anti-tank mines World War II infantry weapons of the United States Military equipment introduced from 1940 to 1944 {{Landmine-stub