Lenntek Sonix Ultra Lightweight Premium Aluminum Earphones - 2 Pack - Black Includes: 2 Sonix Earphones, 2 Hard Cases, 2 Velvet Pouches, 2 Extension Cables (2ft Long), 10 Sets of Soft Silicone Ear Seals (xS, S, M, L) Sensitivity (Efficiency): 100dB SPL / 1mW @ 1 KHz, Frequency Response: 10Hz to 20KHz, Impedance: 32 Ohms 8mm balanced premium neodymium magnet drivers, Gold plated 3.5mm (1/8th") stereo plug Braided tangle resistant nylon cable; Durable 45 deg angle golded plated plug Custom tuned premimum allow earphone case; Ultra light weight and size for better fit and comfort