Sennheiser HD 25-SP Headphones Reproduction of high sound pressure levels across the frequency range allows for critical and enjoyable listening in a noisy environment. The sturdy lightweight, closed dynamic HD 25SP offers up to 16 dB of passive noise attenuation. Features: - Sturdy, modular design for durability - Lightweight and comfortable - High maximum sound pressure level - Neodymium ferrous magnet systems and lightweight aluminum/copper voice coils for high transient response.