The HS9000 headset has a 2.5mm plug to fit cordless, cellular and many "consumer" and small business corded phones. The microphone has a foam windscreen to minimize noise transmission when used outdoors, and a long boom to reach directly in front of your mouth for strong voice output. The swivel design allows the earpiece and microphone to be used on your left or right side. It has no clothing clip. We have tested this headset and found it suitable for many cordless phones, as well as cellphones and corded phones with 2.5mm jacks.