The active loop allow to wake up RF transponder and RF-S transponder. The active loop is connected to the RF decoder.
Two waterproof push buttons make it possible to program the loop ID and the power of transmission.
The loop is generally put under the road but for non motorized sports it is possible to fix it with tape.
The maximum width of the track is 30 m (98 ft) and the spacing of the wires should be 80 cm.