Yealink Replacement Headset for WH62/WH66 Single Ear The Yealink WHM621UC is a replacement headset for the WH62/WH66 DECT Wireless Mono Headset. It works seamlessly with major UC platforms like Microsoft Teams and integrates natively with Yealink IP phones. Designed with a soft leather ear cushion, the WH621UC provides all-day wearing comfort.