There is now an official calibration lab for Met One Instruments, Inc. particle counters and samplers in China........ Calibrations will be performed under the company name “Qingdao Kangbao En vironmental Equipment Co .” The address is A601 No. 52 Building, Lavie Community, 702 Shanhe Road, Chengyang District, Qingdao Telephone 86- 532 5877 0800 Cell: 86 113 2502 350 2 Direct contact can also be made with Chen Min at email email@example.com or firstname.lastname@example.org ES-642 PARTICLE SAMPLER Optical sensor in weatherproof case used to continuously monitor, detect and measure particulate concentration up to 100 milligrams per cubic meter. Comes standard with an indoor inlet for TSP measurement. Unit does not include any logging or power source. Screen displays Conc, Temp, Baro, and Flow rate. Serial output only shows concentration and error code if one exists. Analog output is gives a voltage representation of concentration.