SYN8390 Motorola iDEN Hands-Free Headset Fits all Motorola phones (some phones require audio adapter). Earbud with microphone Motorola iDEN hands-free headsets allow private phone calls. Plug directly into the phone. Headsets are compatible with all Motorola headset-compatible phones, non-Motorola phones and products that support a 2.5mm headset jack.