A torque transmission device for a powertrain system is described, and includes a continuously variable unit (CVU) of a continuously variable transmission (CVT) arranged in parallel with a fixed-gear-ratio transmission to transfer torque between a transmission input member and a transmission output member. The fixed-gear-ratio transmission includes first and second planetary gear sets arranged to transfer torque between the transmission input member and the transmission output member in one of a plurality of fixed-gear-ratio modes by selectively activating a plurality of transmission clutches. The transmission input member rotatably couples to one of the nodes of the first planetary gear set and one of the nodes of the second planetary gear set. The torque transmission device transfers torque in one of a continuously variable mode, a fixed underdrive input/output speed ratio, or a fixed overdrive input/output speed ratio.