This slightly larger hygrometer is used to accurately measure humidity. If you keep it in your case or in your practice room, you’ll have an accurate idea of just how much humidity is at work. Too dry an environment can lead to cracks, too much moisture can eventually invite mildew and leave pads sticky. Right around 40% – 50% is what to shoot for.
This unit is safe and easy to fit in your case. This model measures 3/4″ x 2.5″. Protect your investment.