24 zones Battery backup walk through metal detector with DSP technology ,multifunction with remoter controller ... requirements. Preset the metal size, weight, volume, location to exclude the coin, key, belt..Sound Alarm: 1- ... metal detector XYT2101LCD is popular used in Airport, banks, Embassies, Jail, Entertainment places, Gymnasiums, Exhibition Center ..etc Walk through Metal Detector ZLZX2101-series ...