Implement-carrying rear carriage comprising: - an internal combustion engine or ICE, preferably of the power pack kind, i.e. complete with silencer, fuel tank, cooling circuit, electrical and/or manual starting system; - a transmission casing assembly to which the internal combustion engine is directly flanged and from which a power take-off shaft projects at the rear, i.e. on the opposite side to the engine; - a three point implement-carrying linkage; - a connecting drawbar featuring a coupling system equipped with a steering articulation on a fork; - a single axle, said power take-off shaft being arranged to power agricultural implements and to allow a fast implement replacement, whereby: - if said rear carriage is coupled, in use, to a single axle self-propelled machine, a vehicle of the hybrid tractor kind is formed since two independent power sources are provided, where the engine of the self-propelled machine causes the forward movement, the engine of the rear carriage supplies the power take-off with power and the implement is defined as a mounted implement; - if said rear carriage is coupled, in use, to a self-propelled vehicle with two or more axles, the driver, while sitting on said vehicle, controls the way the vehicle is driven and controls the functions of the rear carriage being towed, the rear carriage and the implement mounted thereon forming an operating machine that is defined as a towed machine; - in both cases, the operation of the implement for agricultural or gardening activities is independent of the forward movement and the kind of vehicle by which the rear carriage is towed and vice versa; said rear carriage being characterised in that it further comprises - a driver's seat and footboard, - in that the single axle supports two idle shafts with respective braking systems and is equipped at its ends with a pair of wheels having a keying system arranged to provide variable track widths; in that - said coupling system is further equipped with a transverse joint; and in that - when said rear carriage is coupled, in use, to the single axle self-propelled machine, the driver, while sitting on the seat, controls the way the self-propelled machine is driven and controls the functions of the rear carriage on which he is sitting. - an internal combustion engine or ICE, preferably of the power pack kind, i.e. complete with silencer, fuel tank, cooling circuit, electrical and/or manual starting system; - a transmission casing assembly to which the internal combustion engine is directly flanged and from which a power take-off shaft projects at the rear, i.e. on the opposite side to the engine; - a three point implement-carrying linkage; - a connecting drawbar featuring a coupling system equipped with a steering articulation on a fork; - a single axle, - if said rear carriage is coupled, in use, to a single axle self-propelled machine, a vehicle of the hybrid tractor kind is formed since two independent power sources are provided, where the engine of the self-propelled machine causes the forward movement, the engine of the rear carriage supplies the power take-off with power and the implement is defined as a mounted implement; - if said rear carriage is coupled, in use, to a self-propelled vehicle with two or more axles, the driver, while sitting on said vehicle, controls the way the vehicle is driven and controls the functions of the rear carriage being towed, the rear carriage and the implement mounted thereon forming an operating machine that is defined as a towed machine; - in both cases, the operation of the implement for agricultural or gardening activities is independent of the forward movement and the kind of vehicle by which the rear carriage is towed and vice versa; - a driver's seat and footboard, - in that the single axle supports two idle shafts with respective braking systems and is equipped at its ends with a pair of wheels having a keying system arranged to provide variable track widths; - said coupling system is further equipped with a transverse joint; and in that - when said rear carriage is coupled, in use, to the single axle self-propelled machine, the driver, while sitting on the seat, controls the way the self-propelled machine is driven and controls the functions of the rear carriage on which he is sitting.