Onset H21-USB HOBO USB Micro Station Data Logger (-20°~50°C/-40~70°C)

Operating Range: -20° to 50°C (-4° to 122°F) with alkaline batteries; -40 to 70°C (-40 to 158°F) with lithium batteries 

Smart Sensor Connectors: 5 

Smart Sensor Data Channels: Maximum of 15 (some smart sensors use more than one data channel)

Smart Sensor Network Cable Length: 100 m (328 ft) maximum 

Logging Interval: 1 second to 18 hours 

Memory: 512 KB nonvolatile flash data storage 

Time Accuracy: 0 to 2 seconds for the first data point and ±5 seconds per week at 25°C (77°F) 

Battery Type: Four AA 1.5 V alkaline batteries for operating conditions of -20° to 50°C (-4° to 122°F); four AA 1.5 V lithium batteries for operating conditions of -40 to 70°C (-40 to 158°F) 

Communication Type: USB 2.0 interface  

Dimensions: 17.04 x 11.94 x 4.47 cm (6.71 x 4.70 x 1.76 in.)

Weight: 414 g (14.6 oz)

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