The new Mercedes-Benz GLB has been revealed not even two months after the unveiling of the concept ... and, like that show car, it features an optional third row of seats.

In fact, the Stuttgart-based firm says the fresh-faced GLB is the first in its segment to be offered with seven seats, claiming the two retractable perches in row three can be used by people “up to 1,68 metres in height”. Passengers back there gain drinks holders between the seats as well as two stowage compartments on the left and right in the load compartment trim, each with a USB port.

Slotting neatly between the GLA and recently facelifted GLC, the newcomer measures 4 634 mm long, 1 834 mm wide and 1 658 mm tall (or 1 662 mm in the case of the seven-seater), with a wheelbase of 2 829 mm (that’s some 100 mm more between the axles than the latest B-Class, in case you were wondering).

Mercedes claims headroom in the first row is a best-in-segment 1 035 mm, while the five-seater model offers a generous 967 mm of rear legroom and luggage volume from 560 to 1 755 litres, depending on the position of the seats. Optionally, the second row can be longitudinally adjusted and as standard the backrests back there are adjustable in several stages.

The new GLB draws its power from a range of familiar four-cylinder petrol and diesel engines already used elsewhere in the brand's compact vehicle line-up. The GLB200, for example, employs the 1,33-litre petrol unit (co-developed with Renault) offering 120 kW and 250 N.m to the front wheels via a seven-speed dual-clutch transmission.

The GLB250 4Matic, meanwhile, uses a 2,0-litre four-pot worth 165 kW and 350 N.m, directed to all four wheels via an eight-speeder. Then there’s the 2,0-litre turbodiesel in the GLB 200d and GLB 220d (each also featuring eight-speed gearboxes), churning out 110 kW/320 N.m in the case of the former and 140 kW/400 N.m in the case of the latter.

An "Off-road Engineering" package will also be offered for models equipped with 4Matic, featuring a driving mode that adapts the engine's power delivery and the ABS control to “easy off-road terrain away from tarmac roads”. The package also includes an "animation of the driving situation" in the media display, a downhill speed regulation function and (in combination with Multibeam LED headlamps) an off-road lighting function.

The new GLB will be built at the Aguascalientes plant in Mexico (and in Beijing for the Chinese market).