Sennheiser’s Circle Series, our popular range of robust, wired headsets, has proven to be a lasting favorite with contact centers, offices and Unified Communication professionals around the world – and for good reason: In increasingly stressful workplaces, being able to hear and be heard clearly is critical to performance – and long-term comfort is essential for all day users to maintain their focus and energy. With Sennheiser Voice Clarity, noise-cancelling microphone for noisy environments and a lightweight, ergonomic design for all day use, a Circle headset is simply the perfect tool when clear communication and long-term user comfort are crucial to the job in hand.Choosing the right Circle:SC 230 USB MS IIA premium single-sided wired headset for quality-conscious contact center and office professionals requiring outstanding sound performance while maintaining contact with their surroundings.SC 230 USB CTRL II A premium single-sided wired headset with built in call control unit for quality-conscious contact center, office and UC professionals requiring outstanding sound performance while maintaining contact with their surroundings.SC 260 USB MS IIA premium double-sided wired headset for quality-conscious contact center and office professionals requiring outstanding sound performance in noisy environments.SC 260 USB CTRL IIA premium double-sided wired USB headset with built in call control unit for quality-conscious contact center, office and UC professionals requiring outstanding sound performance in noisy environments and best quality sound from double-sided neodymium speakers.