Busy Beacon Universal Online Indicator and Busy Light for Headsets and Phones, Works with Sennheiser, Plantronics, Jabra, VXI Easy to see - the sleek design is easily seen from every angle Universal compatibility - the Busy Beacon is guaranteed compatible with 98% of office phones and headsets You're in control - the adjustable fade controller lets you decide how long the red light glows after your conversation goes quiet Do not disturb mode - not on the phone, but still want to be left alone Install in seconds - quickly connects to your phone, headset and usb port for power