Splits in the soundboard,protruding fret ends and concave soundboards
Maintaining a reasonable humidity level can help prevent these problems.
note:thes humidifier is intended for use with a guitar inside a Ukulele case.
It will have little or no effect outside of a case
Hold the latex tube under water for about 30seconds.
gently squeeze excess water from the tube and wipe the outer surface dry.
place the tube inside the Ukulele through the soundhole through the middle two strings.
place the tube inside the violin through the soundhole

leave the rubber plate sitting on top of the strings
this will make it easy to remove the humidifier after use
place the Ukulele in its case and lose the case.

the humidifier is not intended to stay in the Ukulele during playing
it should only be used in dry conditions as adding moisture in humid conditions may cause the guitar to swell
the humidifier should be moistened under water every time it is re-used as the tube will dry out very quickly in the open air.