Using the Polaris models from Plantronics, you can easily and cost-effectively add hands-free efficiency to phone systems that already have built-in amplifiers and volume controls. Just plug in the Polaris headset and you're ready to take full advantage of your phone system's built-in headset amplification and controls. Like all Plantronics' products, the Polaris models deliver no-compromise audio quality and ease-of-use. Polaris models let you get the most out of the built-in capabilities of your phone system.The most popular headset in the world, the Supra owes its popularity to the perfect balance between light weight, superior sound and outstanding comfort. The dual earpieces have a yoked double cable, which gives greater clarity by providing sound in both ears. Polaris models are for use with phone systems with built-in amplifiers.By eliminating up to 75% of all office background noise, the Supra Monaural Noise Cancelling Headset with its unidirectional microphone makes the wearer's speech much clearer. As a result, calls can be completed faster and there is less likelihood of a misunderstanding during the call.