Product details:

Map the migration of water in carpet and pad without straining your back. The HydroSensor II has a collapsible shaft that extends to 31" to save your knees and posture. Sensitive nickel-plated points alert you to moisture content above 17 percent. Use only on carpet and pad. Extends to 31" for use, Collapses to 21" for storage, Stainless steel construction, Nickel-plated and retractable points.