Advantages: Product Features: 1. Industry's first record-keeping noise detector 1, with backlit LCD display 2. Automatic Capture 2, maximum and minimum / Data Hold 3. Max / Min / Hold 3, fast / slow Speed ??time-weighted 4. Supporting the industry's first professional tripod can be fixed measuring 4, A / C frequency weighting sound level 5. Up to 5 shows the median industry, wide range 130dB 6, accurate measurement noise, 0.1dB resolution 7, high / medium / low / 8 automatic 4-band measurements, frequency response: 31.5Hz ~ 8kHz 9, test recording data storage technology indicators: time-weighted fast (Fast) 125 ms; slow (Slow) 1 sec Resolution 0.1dB accuracy 1.4dB Frequency Response 31Hz ~ 8kHz 4 digit display, numerical Update 2 times / sec analog bar fast analog display (20 / S) data store 50 groups of 1/2 inch polarized condenser microphone automatically shut down 15 minutes without any operation After the high-frequency range of the low-frequency 30-80dB IF 50-100dB 80-130dB automatic 30 ~ 130dB Dimensions 210x55x32 mm Weight 230 g (including battery) Application: 1. Coal Mine Safety Regulations seven hundred and fortieth an explicit provision is necessary to detect the noise decibels, the noise damage control, reduce accidents. 2. Mining Group Occupational Disease Prevention Center, mine ventilation and fire prevention department, department of electrical and mechanical mine safety supervision bureau of occupational health departments, mine safety evaluation agencies.