Features: Professional Radiation Dose Alarm Instrument: adopts GM counter tube, it is mainly used to monitor X, Y, and rays with highly sensitivity and accurate measurement. OLED display screen: display the instantaneous dose, average dose and cumulative dose rate clearly, visual in night. Easy to Use: one button startup and test automatically, and with audible and visual alarm if the test result is over the limit. Rechargeable & Reusable Battery: Built in lithium battery power supply, power saving and durable. Super Mini Size: with 0.7oz lightweight and the size as small as a lipstick, the nuclear radiation detector is very convenient to carry. Specifications: Material: ABS Sensor: 48mm Geiger counter tube Measure Range: 0.05uSv-50mSv Measure Precision: -17%...+25% based on 137Csy Charging Time: 2-3 hours Alarm Responding Time: <10s Battery: 3.7V, 300mAh lithium battery Working Environment: Temperature -20~50, humidity <95%RH without dew Item Size: 108 * 18 * 15.3mm / 4.25 * 0.71 * 0.60in Item Weight: 19g / 0.66oz Package Weight: 97g / 3.42oz Package Size: 14.2 * 6.8 * 2.9cm / 5.59 * 2.68 * 1.14in Package List: 1 * Geiger Counter 1 * Type-C Cable 1 * Manual (English)