1) Accuracy class: class 2 2) International Electro-technical Commission IEC521-1988 standards 3) High accuracy, wide load range, and stable and reliable operation 4) Twin-gem bearing 5) Reference voltage: 220V 6) Reference frequency: 50Hz 7) For indoor use with the following conditions: a) Temperature range: -30C to 55C b) Relative humidity not to exceed 95% c) The surrounding air should be free of active gases, dust, salt mist, mildew and mold Inner packing: Dimensions: 185 x 140 x 130mm Weight: 1,450g