PMX200 Powerful Bass Headphones bring a high-efficiency, low cost, and trendy street-style look. This is the sealed-back version of the PMX 100 neckband headphone. Same basic design and ergonomics but in closed earcup construction providing about 8dB of external noise attenuation. You would be hard pressed to find another sealed back neckband deliver this kind of performance, at such a great value. Designed for compatability with all portable and home music players--such as MP3s & Satellite radio receivers--these headphones are destined to meet all of your functionality needs. The PMX200 low 32-ohm impedance and 114dB sensitivity rating should provide more than enough volume output from any audio source. Sennheiser We are proud to bring the Sennheiser line of product to satellite radio. They make quality, long-lasting headphones that are built to please. Sennheiser is recognized as the world leader in microphone technology, RF-wireless and infrared sound transmission, headphone reducer technology, and active noise-cancelling. Their variety of products are made to fit everyones needs. If you are a tough person to satisfy, Sennheiser is the way to go. Package Details: Includes: • PMX200 Headphones Product Features: Compatability: Great for use with Mobile MP3 players and Gaming Consoles Powerful: Powerful sound reproduction due to neodymium magnets, Duofol diaphrams and TWIN attenuation System Boost: Closed construction efficiently boosts bass performance and shields ambient noise Light: Lightweight, metal-reinforced adjustable neckband for perfect fit Technical Specifications: Model #: PMX200 Manufacturer: Sennheiser Weight: 2 lbs. Available Documentation: In order to view our radio hardware manuals online, you will need to have Adobes Acrobat Reader installed on your computer. If you do not yet have Acrobat Reader, please visit Adobes web site to download the reader free of charge. PMX200 Neck-Worn Sennheiser Headphones User Guide (n/a)