OZM-4

Both OZM-3 and OZM-4 have cast iron fragmenting bodies while the OZM-72 also contains preformed steel fragments, and all three are issued with empty fuze wells, so a variety of fuzing options are possible.

The mines can be activated by a variety of fuzes, including electronic fuzes or command initiation, although they are most commonly fitted with an MUV booby trap switch which is activated by a tripwire. On firing, a metal base plate remains in the ground, while the mine body is thrown up by a small lifting charge, but remains attached to a strong wire tether. When the end of the tether is reached at a height of approximately 0.5 m, the main charge explodes and scatters fragments of the casing across a wide area. OZM mine may sometimes be laid directly on top of an MS-3 mine. The MS-3 is an anti-handling device which closely resembles a PMN mine, except that it has a "blister" on top and operates purely as a pressure-release boobytrap. Lifting an OZM mine (without rendering safe the MS-3 placed underneath) will trigger detonation.

• Illustration — Soviet Anti-personnel landmines OZM-72, without and with fuse

• Casing material — cast iron • Weight — 3.2 kg (7 lbs) • Fragmentation charge (TNT) — 75 gr (0.16 lbs) • Casing diameter — 76 mm (3 inches) • Casing height — 130 mm (5.1 inches) • Length of the sensor target (one-way) — 5 meters (16.4 ft) • Sensor sensitivity — 0.5–1 kg (1.1 - 2.2 lbs) • Radius of guaranteed lethal destruction — 9 meters (29.5 ft) • Temperature usage range — -40 to +50*C (-40 to +138*F) • Sources

• Casing material — cast iron • Weight — 5.4 kg (12 lb) • Fragmentation charge (TNT) — 170 gr (0.39 lb) • Casing diameter — 90 mm (3.5 inches) • Casing height — 170 mm (6.7 inches) • Length of the sensor target (one-way) — 10 meters (33 ft) • Sensor sensitivity — 0.5–1 kg (1.1 - 2.2 lbs) • Radius of guaranteed lethal destruction — 13 meters (42 ft) • Temperature usage range — -40 to +50*C (-40 to +138*F) • Sources

• Casing material — iron • Weight — 5 kg (11 lbs) • Fragmentation charge (TNT) — 660 gr (1.49 lb) • Casing diameter — 108 mm (4.1 inches) • Casing height — 172 mm (6.7 inches) • Sensor sensitivity — 1.5–6 kg (3.3 - 13.2 lbs) with MUV-3 fuse • Radius of guaranteed lethal destruction — 25 meters (82.5 ft) • Radius of fragments — 50 meters (164 ft) • Temperature usage range — -40 to +50*C (-40 to +138*F) • Number of preformed steel fragments — 2400 pcs. • Sources

Since the Ottawa Treaty, a number of countries have decided to retain their OZM mines, but convert them to command detonation only by destroying all fuzes which can be indiscriminately activated – potentially by non-combatants or animals. Belarus in particular has decided to keep 200,000 OZM-72.