The FiiO FD3 is an in-ear headphone featuring a dynamic driver and a semi-open acoustic design. The driver diaphragm is made from Diamond-Like Carbon, a material that is almost as rigid as a diamond. The diaphragm is extremely lightweight and responds particularly quickly to impulses, allowing the FiiO FD3 to reproduce music with fine detail and free from coloration. The diaphragm is powered by a magnet with 1.5 Tesla, enabling very robust bass and excellent high-frequency resolution. The semi-open design provides a particularly natural sound, and the pressure equalization reduces strain on the eardrum, preventing fatigue even after hours of listening. The FD3's housing is made from very lightweight aluminum and magnesium, and the top has been enhanced with 2.5D glass for a great look. The braided earphone cable is made from monocrystalline copper and features a 3.5 mm plug with MMCX connectors, allowing for easy cable replacement if needed. Good sound goes hand in hand with an optimal fit, which is why the FD3 earphones come with various ear tips in different sizes and shapes, as well as with different sound signatures. For further sound customization, two interchangeable sound tubes are included: the larger black sound tube provides particularly detailed highs, while the smaller red sound tube delivers robust bass. Additionally, you will receive a sturdy hard case to securely store and transport your earphones and accessories.