The YHA-EH-ET contains one earhook and four pairs of eartips for Yealink WH63/WH67 DECT Convertible Wireless Headsets. The earhook helps secure the WH63/WH67 on the ear, preventing interruptions during a call. It has four pairs of eartips, each with a unique design and size. It lets users pick the one that best fits their ears, ensuring all-day wearing comfort. Instruction: For Right ear 1. Align the earhook ( insert it onto the headset. Be sure the earhook is flat against the headset and rotate the earhook up 90°. 2. Choose the size of eartip that fits most comfortably. Align the eartip with the notch facing the microphone as shown. Press on to attach. For Left ear: The difference between the right ear and the left ear assembly is that the direction of the earhook is different.