3-tone Audio Discrimination: once the metal finder detect something, it will sound 3 distinctive tones(high, medium, and low) for different types of metal. Sensitivity Adjustment: after you become familiar with how the detector works, it is important to fine tune the sensitivity to get better detecting effect. Easy to Assemble & Operate metal detector is easy to assemble no tools are required When detecting, keep the search coil parallel to the ground, then sweep it from side to side slowly. Height Adjustable: user-friendly stretchable rod, allows the operator of different heights to adjust the detector to the desired position for comfortable using. Headphone Jack: detector designed with a 3.5mm headphone jack for connecting with headphones(NOT included). Using headphones not only allows you to hear subtle changes in the sound more clearly, but also prevents the sounds from bothering bystanders., Manufacturer: MTHCKXJBSUZ