Professional Metal Detector Treasure Hunter PL-2 Ground Balance function: automatic and also manually adjustable. Manual ground balance has two modes to improve the detection precision. Automatic and manual adjustment to eliminate mineralization reaction. Identify/reject metal function to eliminate unwanted metal target. Metal scan and metal type modes switchable. Metal scan mode with the technology to eliminate mineralization reaction and preferable sensitivity. After a target is found, choose Metal Type mode to discriminate non-ferrous metals and ferrous metal. LCD display.Speaker indication and headphone jack option for sound alarm. Night hunting light and LCD back light. Low battery indicator. Lead wire disconnection alarm. with a carrying case. Max. detection depth: 1.5 meter for a 50 cm x 50 cm x 1.2 cm aluminum board). 23cm for a Quarters of USD. The maximum detection depth can be reached 6 meter desponds on the metal size. Detection mode: metal scan mode and metal type mode. Principal vibration frequency: 4.19 MHz. Signal frequency: 7.2KHz. Search coil: 12 inches in diameter. Power supply: DC 9V (6 x 1.5 V AA batteries -- not included in this package). Stand-by-current: 40 MA. Low Battery: 7.2V +-0.2V. Weight: 4lbs 5 oz.