M14 mine

The M14 mine is a small (56 mm [2.2 in] diameter) anti-personnel land mine first deployed by the U.S. circa 1955. The M14 mechanism uses a belleville spring to flip a firing pin downwards into a stab detonator when pressure is applied. Once deployed, the M14 is very difficult to detect because it is a minimum metal mine, i.e. most of its components are plastic. Because of this, the design was later modified to ease mine clearance via the addition of a steel washer, glued onto the base of the mine. It was commonly known as the "toe-popper" or "plastic mine."

In order to activate the M14, the base plug is removed and discarded and an M46 stab detonator is screwed into the base of the mine. Then the mine is placed into a shallow hole in the ground (flush with the surface) and the pressure plate is carefully rotated from its safety position to the armed position using the special arming spanner supplied in each crate of mines. Finally, the U-shaped metal safety clip is removed from the pressure plate by pulling on the attached cord. At this point, the mine is fully armed. When deployed by the USA, M14s are often laid together with other mines in their inventory i.e. the M16, M15 or M19. In a "mixed minefield" the anti-tank mines protect anti-personnel mines and vice versa. Similarly, M14s can be laid among other mine-types manufactured by different nations e.g. alongside the PMA-2, VS-50, Valmara 69 or TM-62.

The top of an M14 has a simple arming indicator (an arrow embossed on the pressure plate) which can point to either A(rmed) or S(afe), giving a clear indication of its status. When the arrow points to "A", the M14 will detonate if stepped on. Disarming the M14 requires the arming steps to be performed in reverse. However, due to the possibility of a booby trap or some other type of anti-handling device being fitted underneath, it is often standard demining practice to destroy land mines in situ, without attempting to remove and disarm them.

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