This sound hole humidifier is made of ABS material with good texture and can provide you with good service. This sound hole humidifier has a simple design and practical functions, designed with a precise indicating needle hygrometer, widely used in folk acoustic guitar. Features -Color:Black -Material:ABS -Size:10.80X10.80X1.50cm/4.24X4.24X0.59in - Acoustic guitar humidifier with hygrometer is essential for maintaining the proper humidity levels that your guitar need. - Guitar humidifier provides the that your guitar needs to damages that can be caused by changes in humidity. - Guitar humidifier with hygrometer protects your guitar from the effects of dry weather and destroy your guitar. - With the help of our sound hole humidifier with hygrometer, you can repairs and prolong the life of your instrument. - Humidifier with hygrometer is designed with a precise indicating needle, makes it easier to monitor changes in humidity. Package list: 1 x Guitar Humidifier with Hygrometer