Features: It is mainly responsible for monitoring the radiation of X, r and hard ray in various radioactive work areas. Wide application: it can be used for nuclear power plant, accelerator, iron and steel industry, chemical industry, r radiation, radioactive laboratory and surrounding environment monitor of nuclear facilities. Two alarm methods support: sounds and vibrations two alarm ways You can set the alarm value by yourself. It can automatically store the last measured data when the power is off, so that your data is not easy to lose. It supports two measurement modes: quick and smooth mode. It has the maximum value hold function, which can automatically maintain the maximum value. Specifications: Material: ABS Sensors type: Geiger counter Measuring ranges: 0.00-1000uSv/h Measurement accuracy: 15% +6/p Energy response ranges: : 0.1&65374;1.25Mev Beta&65306;0.25&65374;3.5Mev X: 0.03&65374;3.0Mev Measurement unit: uSv/h, mR/h Cumulative time: 1-9999 minutes can be set Operating temperature: -30&8451;~60&8451; Working humidity: 5%-95%RH (no condensation) Power: 1 * AA battery (NOT included) Package size: 90 * 80 * 45mm / 3.5 * 3.1 * 1.8in Package weight: 150g / 5.3ounce Packing list: 1 * Geiger Counter