A powertrain for a Mild Hybrid vehicle, said powertrain comprising: - an engine ; - a driveline including a gearbox having an input shaft connected to the engine , an output shaft to be connected to driving wheels of the vehicle and a countershaft couplable to the input shaft for transmitting a rotation of the input shaft to the output shaft ; - an electric machine ; - a coupling , in the form of a power take-off (PTO), which is connected to the countershaft , and configured to be coupled to a fitting of an auxiliary ; - a gear reduction mechanism having a free wheel and at least three separate and rotatable junction elements, said junction elements including: - a first junction element that is connected to the electric machine ; - a second junction element that is connectable to the free wheel ; and - a third junction element ; characterized in that the rotational speeds of the junction elements are interdependent but do not have a fixed ratio relative to one another, said third junction element being connected to the countershaft ; wherein the torque ratio between the third junction element and the first junction element can be selected from at least two different ratios, namely a first ratio and a second ratio; said coupling being arranged at one end of a shaft which, in the mounted position, is an extension of the countershaft or is configured to have the same rotational speed as the countershaft , the powertrain further comprising an additional gearing mechanism as a connecting mechanism between the third junction element and the countershaft , the additional gearing mechanism being configured to create an offset along a direction orthogonal to the longitudinal direction (X), in the mounted position, between the countershaft and the first junction element . - an engine ; - a driveline including a gearbox having an input shaft connected to the engine , an output shaft to be connected to driving wheels of the vehicle and a countershaft couplable to the input shaft for transmitting a rotation of the input shaft to the output shaft ; - an electric machine ; - a coupling , in the form of a power take-off (PTO), which is connected to the countershaft , and configured to be coupled to a fitting of an auxiliary ; - a gear reduction mechanism having a free wheel and at least three separate and rotatable junction elements, said junction elements including: - a first junction element that is connected to the electric machine ; - a second junction element that is connectable to the free wheel ; and - a third junction element ; - a first junction element that is connected to the electric machine ; - a second junction element that is connectable to the free wheel ; and - a third junction element ; characterized in that the rotational speeds of the junction elements are interdependent but do not have a fixed ratio relative to one another, said third junction element being connected to the countershaft ; wherein the torque ratio between the third junction element and the first junction element can be selected from at least two different ratios, namely a first ratio and a second ratio; said coupling being arranged at one end of a shaft which, in the mounted position, is an extension of the countershaft or is configured to have the same rotational speed as the countershaft , the powertrain further comprising an additional gearing mechanism as a connecting mechanism between the third junction element and the countershaft , the additional gearing mechanism being configured to create an offset along a direction orthogonal to the longitudinal direction (X), in the mounted position, between the countershaft and the first junction element . <EOS>