Features:- >Drum shaped cavity design. >Lightweight Aluminum Alloy Ear Cavities. >Bass Enhancing Acoustic-Flute Design. >Large 14.2mm dynamic driver. >Beryllium-plated Dome structure+PU gasket diaphragm. >Imported Daikoku voice coil. >Detachable Cable With 2-pin Connectors. > High-purity monocrystalline Copper Silver-Plated Cable. >Twist-Lock Swappable Termination Plug System. >Magnificent sound performance. >Powerful Sound Output. >Comfortable Wearing. Technical Specs:- >Impedance: 45Ω. >Frequency response range: 20Hz-20kHz. >Sensitivity: 105dB. >Max input power: 100mW. >Termination plugs: 3.5mm/4.4mm. >Two-Pin Connectors. >Cable length: 120cm approximately. >Weight: 3.9grams. FiiO FF3S is a redesigned upgraded version of the FF3 flat-head earbuds from FiiO. With a completely redesigned aluminium-alloy cavity structure, the FF3S now has enhanced sound performance with ultra-lightweight aesthetics. The pair weighs only 3.9 grams for each ear shell promising great comfort while listening to your favorite music. With a Dual-Drum cavity design and bass-enhancing acoustic-flute structure, the FiiO FF3S delivers an impressive listening experience!! Ultra Lightweight Aluminum Alloy Build Structure:- Based on the user feedback for the original FF3, FiiO has redesigned the cavity of the FF3S with lightweight aluminium alloy cavities. The shells are extremely lightweight with just 3.9 grams for each side. It provides enhanced wearing comfort with no pressure on the ear canal, the pair literally disappears into your ears. Explosive Sound With Large Dynamic Driver:- FiiO FF3S adopts a 14.2mm large-sized dynamic driver unit. It features a high-quality beryllium-plated dome with PU gasket suspension delivering quality sound with low distortion. FiiO has tuned the pair with professional adjustments to achieve ultimate performance complementing different genres of music well. Drum-Like Cavity Design:- FiiO FF3S features a dual “Drum” shaped bass cavity design structure. This unique-shaped cavity design enables the FF3S to fully utilise the sound resonance inside the structure and deliver enhanced sound performance. Bass Enhancing Acoustic Flute Design:- FiiO has fitted a bass-enhancing acoustic tube within the unique housing of FF3S. This tube extends the airflow path, increases air damping, and improves sound damping to lower the resonance point of the pair. With this acoustic tube design, the FF3S produces a solid bass response with ultimate performance. High-Purity Cable With Swappable Termination Plugs:- FiiO FF3S comes bundled with a high-purity stock cable. The cable has 0.78mm 2-pin connectors along with FiiO’s self-designed twist-lock swappable termination plug system. Users get 3.5mm and 4.4mm plugs in the package. This cable is made up of high-quality silver-plated monocrystalline copper material that provides clear signal transmission with low internal resistance.