The hygrometer has been delivered in a simple repackaging and had out of the box first be calibrated, as it indicated to high values. Therefore one must it only for about 30 minutes to wrap in a damp towel, to simulate a high humidity and then adjust the pointer with a set screw to 95-97% humidity. After calibrating the hygrometer indicated similar values to two other (more expensive) hygrometer that I own. Very nice, I think the labels, so you can see at first glance, as the humidity in the room is.
The hygrometer has a good price / performance ratio and is ideal for a rough estimate of the humidity in the home.