Eliminate feedback and enhance stage volume.Quick and easy to install & remove.Soft flexible rubber cover, safe for the guitar finish.The Screeching Halt cover works with most pickup systems without disrupting placement or performance.Suitable for 40 inch /41 inch EQ Acoustic Guitar.Color: BlackMaterial: Soft RubberTop diameter: 11cm / 4.3inBottom diameter: 10cm / 3.9inHeight: 1cm / 0.4inWeight: 63g / 2.2oz/pcsNote: Please check the size of your guitar's sound hole to see if this sound hole cover is fit for it.Package includes:2 * Sound Hole coverOnly the above package content, other products are not included.Note: Light reflection 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.