20†x 20†Reusable Cobalt Chloride Moisture & Leak Detection Cloth

20" x 20" cloth can be cut to size and reused, enabling maximum versatility Large cloth size enables you to detect leak patterns in large spaces Let the cloth dry and everything not touched by water will return to blue so you can reuse it ~ it's that easy! Color will change slowly when relatively humidity is over 55% and rapidly when the cloth is wet No color chart or other tools or equipment needed for accurate results