# 3.25 – USB redirection

USB redirection is based on WebUSB: [https://wicg.github.io/webusb/](https://wicg.github.io/webusb/). Please check your browser compatibility: [https://developer.mozilla.org/en-US/docs/Web/API/USB#browser_compatibility](https://developer.mozilla.org/en-US/docs/Web/API/USB#browser_compatibility).
- Add "&mapUSB=on" parameter to your websocket URL to enable it.
- It only works on secure contexts (HTTPS only).
- Feature Policy is needed if the session is running in iframe:<br>`<iframe allow="usb; fullscreen"></iframe>`
- The client try to display all the available USB devices to use. If you want specific device only, you can set up the USB files in appcfg.js: `usb: {filters:[{vendorId:0x2341}]}`
- List of USB ID’s: [http://www.linux-usb.org/usb.ids](http://www.linux-usb.org/usb.ids)