An inexpensive but effective device for monitoring the relative humidity of your piano.  Manufacturers recommend a relative humidity of 42%.  However, we don't all live in an ideal world.  Therefore, a relative humidity of between 50% and 60% is more achievable – (and more in-line with humidity levels found in many homes visited over a 22 year period).  If you find your humidity levels creep into the 70% / 80% then a dampp-chaser is strongly recommended.

Modern pianos are normally more 'tolerant' to their environment – whereas, older instruments generally 'react' far more noticeably.  However, in both cases, maintaining an ideal humidity can cause fewer sticking keys, benefit performance and help to prolong a piano's life.

These great little devices also make a wonderful and helpful gift.