Streamlined design. 2 operation controls. Mode selection switch. Built-in Automatic Ground Trac balances for mineralization while deteching. Detects in extreme ground conditions from salt wet beaches to highly mineralized inland sites w/no operator adjustments to circuitry and no loss of sensitivity. Sensitivity meter helps determine signal strength. User controlled sensitivity and discrimination knobs for varying conditions. headphone jack with 1/4" plug can be used with most headphones.