Abstract: Disclosed is an arrangement for connecting a plurality of transistors to a heat sink surrounding one end of a control motor for a mailing machine. The motor is a conventional bi-directional stepping motor which controls various operational functions of the mailing machine. The direction, speed and continuity of the rotation of the motor rotor are controlled by a plurality of transistors which receive appropriate signals from a microprocessor. The transistors generate a substantial amount of heat during operation of the motor and are mounted on a heat sink connected to the motor in order to dissipate this heat.