SC 135 USB (single-sided) and SC 165 USB (double-sided) are headsets with 3.5 mm jack and detachable USB cable, optimized for UC professionals who value device flexibility, great sound, discreet modern style and comfort. Activate your potential The SC 100 headsets make a great impression. From their contemporary sleek styling to great sound for calls and multimedia, they excel in all areas: at your workstation, on the move around the office or on your commute to work, there is a variant tailored to your needs. With discreet boom arm design, adjustable fit and a choice between acoustic foam or soft leatherette ear pads, the SC 100 headsets are built for flexibility and comfort. Sleek design Looks as good in the office as on the daily commute - with sleek contemporary design and bendable boom arm that folds discreetly into the headband. Great sound Sennheiser HD stereo sound (available on double-sided variants) - for calls or listening to music while working. Plug-n-play connectivity Easy plug-n-play connectivity - with 3.5 mm jack and USB. Travel friendly Easy transportation or storage, thanks to an innovative fold-flat ear cup design. Sennheiser Voice Clarity If you are working in a noisy enovironment, you will benefit from the Voice Clarity technology in Sennheiser headsets. With a noise-cancelling microphone and detailed sound, every word comes through crisp and clear. It's as if you're having a face-to-face conversation.