Fangrui Product Details Portable Hand-held Security Metal Detector (gp 3003b1)(black) 1) Highly Sensitive 2) Simple And Convenient To Use, No Adjustment Is Required; 3) The Detection Distance Will Not Be Changed When The Battery Voltage Drops From 9v To About 7v; 4) Low Power Consumption, Can Work For 40 Hours Continysly; 5) There Is Automatic And Continues Alarm When The Battery Is Used Up; 6) Switch On Off Audio Prompt Function; 7) Witch External Rechargeable Socket Hole; 8) Has Audio, Light And Vibration Hand Off Switch 9) Detection Distance: - Pin: 30-60mm - 64 Model Handgun: 150mm - Diameter: 20mm - Steel Ball: 90mm 10) Install The 6f22 15f8h(9v) Battery (not Included) 11) Power: 270mw 12) Alarm: Vibration And Sound And Light Alarm Simultaneously 13) Detection Sensitivity: As Detect One Yuan Coin, The Detection Distance ≥ 5cm 14) Features And Applications: Scanning Area Is Large, Stable, Durable, Suitable For Less Demanding Sensitivity School And Factory Security Tests 15) Current Work: Sound And Light Is Less Than 47ma, Vibration Less Than 103ma 16) Dimensions: 415mm X 85mm X 45mm