Abstract: A traction device attachable to a tire mounted on a tire rim, the tire defining a pair of substantially annular and substantially opposed tire side walls, the tire also defining a tire thread extending between the tire side side walls, the traction device comprising: a first jaw, the first jaw defining a first jaw free end, the first jaw including a first tire gripping element provided substantially adjacent to the first jaw free end; a second jaw, the second jaw defining a second jaw free end, the second jaw including a second tire gripping element provided substantially adjacent to the second jaw free end; the first and second jaws being operatively coupled to each other so as to be movable between an open configuration and a closed configuration, the first and second tire gripping elements being closer to each other when the first and second jaws are in the closed configuration than when the first and second jaws are in the open configuration; the traction device further comprising a traction element exten

Abstract: Multiple latching relays are driven on their first side by all but one of the parallel outputs of a shift register. Each relay on the same shift register is driven on its second side by the remaining parallel output of the shift register. A clock signal is fed to all shift registers and causes each shift register to shift all of its information one cell on the selected edge of the clock signal. A latch signal or blanking signal is used to prevent the shift registers from outputting their information to the relays during shifting. A serial data message is inputted to the first shift register and then from the first shift register sequentially to all of the other shift registers. The information in the serial data message is such that after shifting of all shift registers is complete the appropriate signal will be on each side of each latching relay to cause it to either change or remain unchanged.