[Nuclear Radiation Detector]This Geiger counter nuclear radiation detector with built-in sensor, fast response time and high accuracy, to detect Gamma, Beta and X-rays. Cumulative dose equivalent: 0-99.999mSv. Energy range: 20KeV-3.0MeV 30%(for 137Cs) [Smart Alarm]Enter the alarm setting option to set the current dose alarm value and the accumulated dose alarm value. Whether the detector screen is in sleep state or in operation,the radiation dose detected exceeds the alarm threshold,the radiation monitor will automatically alarm. Light/Vibration/Sound 3 combined alarm modes to choose. [Multifunctional Geiger Counter]Our the geiger counter has other various setting, such as alarm setting, system clock setting and unit setting & language change,you can operate in English (default) or Chinese. Easy one-handed operation. [Working Principle]It uses a Geiger- counter.Counter for detecting the intensity of ionizing radiation (Beta particles, Gamma rays and x-rays).Use a gas tube or a small chamber as a probe.When the voltage applied to the probe reaches a certain range.Each time the ray is ionized in the tube to produce a pair of ions, it can be amplified to produce an electric pulse of the same size.And recorded by the connected electronic device.The number of rays per unit time thus measured. [Application Areas]Widely applied in the environment where existing ionize radiation. Such as radiation, geological survey, iron, Inspection vehicles, nuclear power plants, industry, radiology, radiology laboratories and so on Power supply : 3 AA batteries (not included) Color: As Shown Material: ABS Package Contents: 1 x Nuclear Radiation Detector 1 x Chinese and English instruction manual Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.