民國64年對冷凍水產品保存溫度要求為-18℃以下，未符合規定者不得進口，因此為確認冷凍食品保存環境，需藉由零下溫度計量測溫度。本設備為-50℃至150℃之類比式零下溫度計。

In 1975, the temperature requirement for the storage of frozen aquatic products was set at below -18°C, and items not meeting this standard were prohibited from import. To ensure compliance with the storage conditions for frozen foods, a sub-zero thermometer is needed to measure the temperature. This equipment is an analog sub-zero thermometer capable of measuring temperatures from -50°C to 150°C.