detonator makes it relatively easy (compared to the PMA-2 and
PMA-3) to detect with a metal-detector. The detonator is initiated
by a friction sensitive compound that can fail when wet. When
the compound dries out, the fuze may then function as designed.
version of the fuze with a plastic cased detonator is reported
to have been made. This would render the mine 'metal-free',
so undetectable with a metal-detector.