A tire parameter monitoring system has a plurality of sensor units for monitoring tire parameters, with each sensor unit mounted with a different vehicle tire. The mask preferably comprises two layers of photoresist separated by a layer of light blocking material. In one embodiment the paddle has a vertical shaft, a plurality of laterally-extending elongated arms attached at first ends to the shaft and at distal second ends to angled plates. A plurality of teeth protrude from the circumferential wall. The second PMOS transistor includes a gate and second P doped source region. A display is provided on which a game played under the control of the controller is displayed, the game displayed on the display comprising a plurality of polyhedral elements, each of which has a plurality of faces with a predetermined indicium being carried on at least one face of each element.