Product name: violin sound hole humidifier Model: General Function: When the weather is dry, humidify the violin to prevent the piano board from deforming and cracking. The following two situations need to be used: From the south to the north, the environment suddenly became dry.Heating in winter, conditioning room, open floor heating, low humidity, dry. Instructions:Immerse the humidifier in clean water and remove it after a few minutes.Squeeze excess water from the top so that the humidifier will not drip anymore, and then wipe off the moisture on the surface of the humidifier.Insert the humidifier into the body of the piano from the F hole, the humidifier will naturally evaporate the water slowly, please humidify the crotch from the inside to outside. Colour:blue Material:Rubber + sponge Size:Length: 30cm Package Contents: 1*violin sound hole humidifier Only the above package content, other products are not included. Note: Light and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.