Minelab X-Terra 505 Metal Detector Minelab's proprietary True Digital VFLEX technology the new class of single frequency detectors change the frequency easily by changing coils Compatible with Low Frequency 3khz Medium Frequency 7kHz and High Frequency 18.75kHz coils 6 accessory coil options offer increased versatility Accurate Ground Balance capability with manual adjustment of 0-50 allows the user to easily adjust mineralization easily Noise Cancel function with 5 manual settings allowing the user to pick the quietest channel for detecting Choice of up to 4 tone IDs plus multi-tone Target ID which allows greater flexibility in deciding how targets are represented