Humidity Indicator Cards — Pack of 25

Description

Reversible cobalt-free humidity indicator cards for dropping into a box, a display case or a store to read the environment where the object actually is, rather than where the wall-mounted logger is. Three spots read across the useful range and change colour reversibly, so a card can be left in place for years and read at a glance during a routine check. Cobalt-free by specification — cobalt chloride cards are the traditional article and are now restricted in many jurisdictions on toxicity grounds, so there is no reason to keep buying them. These are an indicator and not an instrument: they tell you there is a problem in a location you would not otherwise have checked, and then you put a logger in that location. Twenty-five to a pack because the answer to ‘where is the damp’ is always more sensors, not better ones.