Verizon Wireless Flex Grip Headset - Compatible with 3.5mm and 2.5mm Phones 3.5mm Flex Boom Headset. 2.5mm Adapter Included with Extra 2 Ear Sponges Flex Grip provides maximum stability for all-day wearing comfort Attractive design and easy one-handed placement Answer or end calls from the in-line button; button also activates voice dialing Superior Sound Clarity. Noise-canceling Flex Boom microphone reduces background noise so you can be heard clearly