theBoom C Universal Noise Canceling Headset with Standard 2.5mm adaptor included Noise cancelling headset for cell phones, office phones, landlines, computer dictation and voip. Over the head design. Connection to virtually any communications device! theBoom C comes with a universal connector and a standard 2.5mm adaptor. Adaptors for virtually any other cell phone, computer or PDA are also available, so you can connect theBoom to multiple devices. Call 1-888-230-3300 for more information. Unmatched Clarity. Even in the noisiest environment, theBoom's patented technology will allow you to be heard clearly. Boosts your voice and suppresses background noise Proven for years on Wall Street and in Black Hawk Helicopters, theBoom is now available for everyday phone users.