There are two (2) Freezer Cop Thaw Indicators with each order.
The Freezer Cop Thaw Indicator allows you to instantly know if your freezer has thawed and re-frozen while you were away. It's simple and easy to use. Just fill the vial up to the line with water and freeze. Then add the ball and cap and place in your freezer. If the freezer stops working, the ice in the vial will thaw and the ball will drop to the bottom letting you know that something happened to the food in your freezer.