Lascar Electronics EL-USB-LITE USB Temperature Data Logger, 4,000+ readings, 1 month battery life

Simply insert any of these compact, 4.5" (11.4 cm) long loggers into your computer USB port, name it, select high and low alarms if required, and set the logger start time. Once configured, the logger can be removed from the computer to log independently. Data is downloaded back onto the PC where it can be analyzed and viewed as a graph using included software.

The low-cost model EL-USB-LITE stores over 4000 readings and has a fixed 30-minute sampling rate and a measurement range of 14 to 122°F (–10 to 50°C).