Clever Logger DUAL Wireless Temperature Data Logger with Vial plus GlycolDual Logger and Vial plus Glycol to measure internal air temp plus internal liquid temp. Requires existing Clever Logger Gateway and is useful for measuring "lagged" temperature inside the fridge. This logger has two sensors one built in and the other on an external probe. When the probe is placed into a vial of some non freezable liquid (such as glycol), it accurately mimics temperatures experienced by liquid vaccines. The built in sensor reacts