Abstract: A machine for applying labels to products of various sizes employs a movable printer/applicator head. Control circuitry responsive to sensors located along a conveyor by which the products are moved toward the machine generates output signals to an electrical motor which drives the printer/applicator head at a speed defined by the processor output signals. Labels to be printed are supplied to the head from a label supply strip wound on a label supply reel mounted on the stationary part of the machine. The portion of the strip extending between the reel and the head is provided with a loop to assure sufficient length of the strip for free movement by the head. The strip is lengthened by an amount less than the length of a label each time a label is removed and is lengthened by an additional amount each time a short-loop condition is detected.