At present, the MV-5 is the most widely employed Soviet antitank mine fuze, and it is often used in improvised mines.
The original MV-5 had a metal case but the newer models may have a plastic case.
It has a spring loaded, ball release striker with a recess in the pressure cap to free the striker retaining ball.
Pressure depresses the cap and compresses the striker spring.
As the pressure cap moves down, the striker retaining ball escapes into the recess, releasing the striker and starting the firing chain.

Length : 43mm
Diameter : 13mm.
Operating force : 6.8 kg

Photos below © B. Bosman.