The device features broadband pass technology, making it sensitive in detecting electromagnetic fields. It has 5 LED indicators that display different levels of magnetic field strength. Suitable for indoor and outdoor use, it can measure electromagnetic fields emitted by electrical devices and power lines. Detects a wide spectrum of EMF frequencies from 50 to 20,000 Hertz. Helps identify varying levels of electromagnetic field exposure. Simple and user-friendly design. Lightweight and portable. Specifications: Detection range: 0 to 20+ milliGauss (mG) Detection frequency: 50 / 60 Hz (50 to 1,000 Hz - ELF; 1,000 to 20,000 Hz - VLF) Accuracy: +/-5% (Typical) LED indicators: - Green (1): Normal magnetic field (0 - 1.5 mG) - Green (2): Low level magnetic field (1.5 - 2.5 mG) - Yellow: Mid level magnetic field (2.5 - 10 mG) - Orange: High level magnetic field (10 - 20 mG) - Red: Extreme high level magnetic field (20+ mG) Operating temperature: -18°C to 49°C (0°F to 120°F) Power source: 9V battery (not included) Weight: 170g Color: Black Material: ABS, electronic components Dimensions: 14.6 x 5.8 x 25.5 cm Package Contents: 1 x K-II Electromagnetic Field Meter 1 x Instruction Manual Note: The package includes only the items listed above. Other accessories are not included. Slight color variations may occur due to lighting and screen display differences. Measurement error is +/- 1-3 cm.