The M 51 MACI and M 52 MACI (Mine Antichar Indétectable) are French circular minimum metal anti-tank blast mines.
The use a variety of fuzes, a M61 pressure/friction fuze, a "tentacle" fuze with four hoses that triggers the mine when two of the opposite tentacles are crushed, and a tilt rod fuze.
The M51 and M52 are broadly similar with a thin fibreglass cases, the principal difference being the M52 is slightly larger than the M51.
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