AIR COUNTER_S is Japan"s best selling radiation detector for home use manufactured by ST Corporation. The device is equipped with the newly developed photo diode and the microprocessor to measure gamma rays up to 9.99uSv/h (gamma rays only). The photo diode works as a scintillator does in that it converts gamma rays to electrical signals, and then the microprocessor converts the signals to the proportional dose rate in uSv/h (micro Sievert per hour). The photo diode never depletes therefore no calibration is required again.Contents: AIR COUNTER_S comes in retail package, Japanese manual & booklet (no English manual), AA alkaline starter battery, and serial#. English quick start guide will be sent to you via email after order is placed. Plus, a free radioactive test source will be shipped with your order. Request if you don"t need for it.Note: It"s not designed for industrial use. You need a professional grade instrument for that application.1 year limited warranty. LifeTech replaces a defective device. A regular parcel may take 2~5 days depending on the destination. Please contact us for any questions.