An HF RFID device for affixing to a surface of a vehicle tire comprising: a. a unitary body having a bottom surface defined within a bottom surface outer periphery and a top surface ; b. an HF RFID tag embedded within the unitary body in a generally horizontal plane within the unitary body, the RFID tag comprising: i. a coil antenna comprising a single filament coiled in a planar configuration that is coplanar with the horizontal plane, the coil antenna defining a closed shape defining within the plane an interior and an exterior of the closed shape; ii. an HF RFID chip in electric communication with the coil antenna for receiving an interrogation signal over the coil antenna and transmitting back identification information identifying the HF RFID chip; characterized in that the bottom surface comprises an affixing portion that is configured for affixing to the surface of the vehicle tire and a non-affixing portion surrounding the affixing portion at an outer periphery thereof, the unitary body having an affixing body portion overlapping the affixing portion and a floating portior overlapping the non-affixing portion, the floating portion completely surrounding the affixing body portion. a. a unitary body having a bottom surface defined within a bottom surface outer periphery and a top surface ; b. an HF RFID tag embedded within the unitary body in a generally horizontal plane within the unitary body, the RFID tag comprising: i. a coil antenna comprising a single filament coiled in a planar configuration that is coplanar with the horizontal plane, the coil antenna defining a closed shape defining within the plane an interior and an exterior of the closed shape; ii. an HF RFID chip in electric communication with the coil antenna for receiving an interrogation signal over the coil antenna and transmitting back identification information identifying the HF RFID chip; characterized in that the bottom surface comprises an affixing portion that is configured for affixing to the surface of the vehicle tire and a non-affixing portion surrounding the affixing portion at an outer periphery thereof, the unitary body having an affixing body portion overlapping the affixing portion and a floating portior overlapping the non-affixing portion, the floating portion completely surrounding the affixing body portion. i. a coil antenna comprising a single filament coiled in a planar configuration that is coplanar with the horizontal plane, the coil antenna defining a closed shape defining within the plane an interior and an exterior of the closed shape; ii. an HF RFID chip in electric communication with the coil antenna for receiving an interrogation signal over the coil antenna and transmitting back identification information identifying the HF RFID chip; characterized in that the bottom surface comprises an affixing portion that is configured for affixing to the surface of the vehicle tire and a non-affixing portion surrounding the affixing portion at an outer periphery thereof, the unitary body having an affixing body portion overlapping the affixing portion and a floating portior overlapping the non-affixing portion, the floating portion completely surrounding the affixing body portion. <EOS>