For some years Romania built a slightly modified version of the Russian Arzamas Machinery Plant BTR-70 (8 × 8) amphibious Armoured Personnel Carrier (APC) called the TAB-77 and details of this are given in a separate entry.

The TAB-77 was followed in production by the B33 that is essentially the Romanian version of the Russian BTR-80 (8 × 8) APC with some minor modifications to meet Romanian requirements, including the installation of a different diesel engine.

In Romanian Army service the B33 is referred to as the TAB Zimbru with a total of 70 units in service. Production has now been completed.

The hull and turret of the B33 (8 × 8) APC is of all-welded steel armour construction that provides the occupants with protection from 7.62 mm small arms fire and shell splinters.

Over the frontal arc this provides protection against 12.7 × 107 mm B43 rounds fired from a range of 100 m. Over the remainder of the vehicle protection is provided against 7.62 × 39 mm rounds fired from a range of 20 m. The turret is provided with protection against 7.62 × 39 mm rounds fired from 20 m.

The driver is seated at the front of the vehicle on the left side and is provided with a single-piece hatch cover above his position that opens to the right. Arranged around the forward part of his hatch are four day periscopes. One of these can be replaced by a night-vision device.

The commander is seated to the right of the driver and has a single-piece hatch cover that opens forward and can be locked in the vertical position if required. He is also provided with four periscopes and a roof-mounted searchlight that can be operated from within the vehicle.

The commander and driver are each provided with a bulletproof window fitted with a wiper to their immediate front, which can be covered when in a combat area by a shutter hinged at the top. To the right of the commander's windscreen is a firing port.

The one-person manually operated turret is mounted on the roof to the rear of the commander and driver and is armed with a 14.5 mm KPVT machine gun with a 7.62 mm PKT machine gun mounted coaxial.

Mounted coaxial above the two machine guns is an infra-red searchlight and mounted on the turret rear is a bank of six electrically operated 81 mm smoke grenade launchers that fire over the frontal arc.

The troop compartment is in the centre of the vehicle with the troops entering and leaving via a door in the side of the hull between the second and third road wheels.

The lower part of the door folds down to form a step, while the upper part opens to the front. The troop compartment is provided with roof hatches and firing ports with associated vision devices.

Each of the roof hatches has a single circular firing port. The six to eight infantrymen are seated three or four down each side facing outwards on bench seats that are over the under floor mounted transmission and gear divided box.

The engine compartment is at the rear of the hull with the air inlet and outlet louvres in the roof and the exhaust outlets mounted on either side.

The B33 is fully amphibious with the minimum of preparation which includes erecting the trim vane which is folded back onto the glacis plate when not in use, switching on the bilge pumps and extending the snorkel to the turret rear. The vehicle is propelled in the water by a single water-jet mounted at the rear of the hull.

Standard equipment on the B33 includes powered steering on the front four wheels with all tyres being fitted with a central tyre pressure regulation system. This allows the driver to adjust the tyre pressure to suit the type of terrain being crossed.

Mounted at the front of the B33 is a mechanically operated winch driven from the transfer box, which is provided with 60 m of cable and a force of 4,500/6,000 daN. A VHF frequency hopping radio with a range of 20 to 50 km is fitted plus a vehicle intercom system. An automatic fire suppression system is also fitted.

According to the manufacturer, the B33 can be fitted with alternative weapon stations from France (Nexter Systems), Germany (Rheinmetall Landsysteme) and Italy (Oto Melara) armed with various 25 to 30 mm stabilised cannon. As far as it is known, none of these turrets have so far been fitted to the B33 APC for trials purposes. Additional details are given in a separate entry. Zimbru 2000 APC

This is a further development of the B33, which is powered by a Deutz BF 6M 1013 diesel developing 260 hp coupled to an Allison MD 3060 PR automatic transmission. It can be fitted with various types of weapon system, including a turret-mounted 30 mm cannon. As of late 2007 it is understood that this remained at the prototype stage.