Previously only seen underneath hacked test mules, the EQB is shown in the new images with altered and disguised front and rear end and similar aerodynamically-optimised wheels as the larger EQC.
In a move similar to that undertaken with the GLC and its electrically powered sibling, the GLB will provide the basis for the zero-emission EQB model. It will feature uniquely styled front and rear ends, dedicated wheel designs and other detailed design changes that are said to lower its drag coefficient below 0.30Cd.
The EQB is set for UK sales in two years' time and has been conceived to run a further-developed version of the driveline destined for the upcoming EQA hatchback. It will use two electric motors, with one powering the front wheels and the other driving the rear wheels. Little is known about the new model, but insiders say it will have a battery of at least 60kWh in capacity and manage a claimed range of around 310 miles.
The GLB is the eighth model to be based around Mercedes' MFA II platform, and it shares its wheelbase with the China-only long-wheelbase A-Class Saloon. At 2789mm, its wheelbase is 60mm longer than those of the other new A-Class models, while a relatively long rear overhang ensures the GLB provides more luggage space than the original GLA. It's not clear yet whether the EQB will retain the GLB's seven-seat option.
Alongside the EQB, Mercedes also plans to introduce a plug-in petrol-electric hybrid system in the GLC for a claimed electric-only range of 62 miles. It will use a 2.0-litre four-cylinder petrol engine and a gearbox-mounted electric motor to power the front wheels, along with a second motor mounted within a ZF-produced rear axle assembly to power the rear wheels. Energy for the motors is provided by a lithium ion battery packaged within the floor.
Both models are core parts of parent firm Daimler's massive electrification project, in which Mercedes will invest £9bn to produce 130 electrified variants by 2025. The flagship of this range will be the EQS, an electric sibling of the next-generation S-Class.