Feature: High-quality materialsl housing. matte anti-fingerprint, one-button non-slip rotary button, more comfortable touch and scratch resistance than plastic cover<br> USB plug and play. 360-degree rotatable arc button, easy to use (volume adjustment, mute, up and down, pause), and avoid discomfort caused by sharp edges<br> Non-slip mat. There is a soft pad at the bottom, which is stable and non-slip during use<br> Lossless sound quality. Adjust the audio source directly without affecting the audio quality.suitable for use with desktop or laptop<br> Broad compatibility. Support for WIN 7/8/10/XP, for , for VISTA, for Android, for iOS (mobile phone needs a suitable universal serial bus adapter cable)<br> Specification:<br> Name: USB volume controller<br> Installation : USB driver-free<br> Mode: button to switch dual mode<br> Applicable to: for Windows, for OS<br> Note:<br> If your device can use a USB mouse and keyboard, you can also use our USB volume controls.<br> Material: plastic<br> colour: Black<br> Package Contents:<br> 1 x PC Computer Speaker Volume Controller Knob<br> Only the above package content, other products are not included.<br> 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.