Operating frequency: 52kHz +/ - 10% (sine wave)

Sensitivity: ) 5cm (for a US quarter)

Indication: audio alert and LED (red) alert

Audio tone changes as the metal size changes

Blinking green indicator when the unit is working properly

Headphone jack: 1/8-inch (for silent operation)

Low sensitivity: to lower the sensitivity, used in place with interference

LED indicators on both front and back faces are optional

Low battery indication

One 9V battery required