Zhengzhou, where the noise meter relatively complete variety? What brand? Sale have warranty? Product description: noise meter can be used for noise engineering, quality control, health prevention and environmental noise monitoring. Engineering, schools, hospitals, shopping malls, theaters, offices, road traffic, family, audio and other occasions, such as: volume measurement applications. Product Attributes: This product is high-precision instruments, measuring accuracy up to ± 1.5dB. Comply with the International Committee of IEC651 TYPE2 and the American National Standards ANSIS1.4 TYPE2. Design standards: ---- A. International Committee of the IEC651 TYPE2 standard ---- B. American National Standard ANSI S1.4 TYPE2 Measuring range: ---- 30 ~ 130 dBA ---- 35 ~ 130 dBC * Accuracy : ± 1.5 dB * Digital & Resolution: 5 & 0.1 dB * Frequency response: 31.5Hz ~ 8.5KHz * Measuring Range: 30 ~ 130, 40 ~ 90, 50 ~ 100, 60 ~ 110,70 ~ 120,80 ~ 130 * Frequency weighting Product Features: A simulation of the human ear & C Mechanical self noise * Time characteristic selection: fast / slow reaction rate * Sampling frequency: 2 times / sec * Microphone: 1/2 inch condenser microphone AC / DC signal Output * Max Hold * Overload display: OVER / UNDER symbols * Low battery indication Packing: PP Box Color Box * Power: 1.5V AA battery 4 or DC 6V 100mA DC Power Supply * Product size: 256 * 70 * 35 mm * Product Weight: 308 grams (including battery) Instrument Co., Ltd., Zhengzhou Megumi URL www.hm5117.cn Contact: Gujingli 0371 -55,676,313 Fax 0371 -66,227,105 Business QQ: 2417674438 Address: Zhengzhou City, South Street, West Street intersection mouth (Tube City Commission south 300 meters)