This product has been discontinued. Take a look at 42270 - Temperature/Humidity Datalogger.
Extech 42260

42260: Temperature Datalogger

Temperature Datalogger for 42265 docking station kit

The 42260 is an additional Temperature Datalogger for use with Extech 42265 and 42266 Kits. This waterproof (IP65) datalogger records up to 8,000 readings. Three start methods: scheduled, immediate or magnetic. Wide operating temperature range from -40 to 185°F (-40 to 85°C). Multiple dataloggers can be programmed and data downloaded from a single docking station (requires a docking station for initial programming).