T-55M - 70 Finnish T-55A/T-55K tanks were upgraded to T-55M/MK level.
The upgrade consists of Bofors FCS-FV/K fire control system, Mecar M-1000 APFSDS-T ammunition, 71 mm Bofors Lyran illumination grenade mortar, 8x 76 mm Wegmann smoke grenade dischargers, thermal sleeve around gun barrel, 1 million cd IR searchlight, new side skirts and storage boxes, RMSh tracks similar to T-72 and a 12.7 mm ITKK 96 machine gun for the loader.
Additional armour was tested, but not included in the final upgrade.
Some are equipped with KMT-5M mine rollers.

T-55MK - command version of the T-55M upgrade.

KAM-1 - Finnish medium recovery tank built on T-54 hull, developed in 1984.
Prototype only.

KAM-2 - Finnish light recovery tank built on T-54 hull, developed in 1985.
Prototype only.

155GH52-SP-T55 - Finnish 155 mm Tampella type gun mounted on a T-55 chassis.
Prototype only.

ITPSV 90 Marksman - Finnish SPAAG conversion of the Polish T-55AM equipped with the British Marksman turret.
T-55M - 70 Finnish T-55A/T-55K tanks were upgraded to T-55M/MK level. The upgrade consists of Bofors FCS-FV/K fire control system, Mecar M-1000 APFSDS-T ammunition, 71 mm Bofors Lyran illumination grenade mortar, 8x 76 mm Wegmann smoke grenade dischargers, thermal sleeve around gun barrel, 1 million cd IR searchlight, new side skirts and storage boxes, RMSh tracks similar to T-72 and a 12.7 mm ITKK 96 machine gun for the loader. Additional armour was tested, but not included in the final upgrade. Some are equipped with KMT-5M mine rollers.
T-55MK - command version of the T-55M upgrade.
KAM-1 - Finnish medium recovery tank built on T-54 hull, developed in 1984. Prototype only.
KAM-2 - Finnish light recovery tank built on T-54 hull, developed in 1985. Prototype only.
155GH52-SP-T55 - Finnish 155 mm Tampella type gun mounted on a T-55 chassis. Prototype only.
ITPSV 90 Marksman - Finnish SPAAG conversion of the Polish T-55AM equipped with the British Marksman turret.
T-54/T-55 operators and variants