Product Data Type Sampling/Logging Rate Measurement Range Storage Price USB-501-LT Temp. 15-minute sampling rate -10 to +50 °C (+14 to 122 °F) 4K $49 USB-501 Temp. Intervals: 10 sec–12 hrs. -35 to +80 °C (-31 to 176 °F) 16K $59 USB-502 Temp./RH Intervals: 10 sec–12 hrs. -35 to +80 °C (-31 to 176 °F) 16K $79 USB-503 Voltage Intervals: 10 sec–12 hrs. 0 to 30 VDC 32K $69 USB-504 Current Intervals: 10 sec–12 hrs. 4 to 20 MA 32K $69 USB-5201 Temp. 2 S/s to PC; 1 S/s to CF card Sensor dependent (See Specs) 2.3 Million Temp. Values (w/64MB CF Card) $629 USB-5203 Temp. 2 S/s to PC; 1 S/s to CF card Sensor dependent (See Specs) 2.3 Million Temp. Values (w/64MB CF Card) $729