Wetness indicator

A wetness indicator is a common feature in many disposable diapers and toilet training pants.

It is a feature that reacts to exposure of liquid as a way to discourage the wearer to urinate in the training pants, or as an indicator to a caregiver that a diaper needs changing.

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The Wetness indicator on a pair of Huggies Pull-Up's. Left Side is Dry. Right side is with Water poured in.