The PX 100 is a pair of open, dynamic supra-aural mini headphones for mobile players. Their outstanding sound reproduction and foldable design make them ideal for outdoor use and traveling. PRODUCT FEATURES:Dynamic stereo mini headphones;Great for travel and outdoor use with mobile sources such as CD, MD or MP3 players;Fold and flip: registered design allows the ear cups to be turned through 90? and fold the headphones closed (headphones will lock in open and closed positions);1.4 m Kevlar-reinforced OFC copper cable with 3.5 mm stereo jack plug; Fits into the shirt pocket: rugged transport case with cord take-up (145 x 75 x 27 mm);Excellent sound quality for mobile audio sources;High-resolution sound due to Sennheiser "Duofol" diaphragms with spiral embossing (reduces and spreads eigenforms);Strong Neodymium magnets for extremely low distortion;High efficiency and powerful reproduction;Balanced and detailed sound image for all types of music;Crisp and fast bass response due to system "twin damping" with 80ppi polyurethane and special perforated elements;Special baffle (based on the legendary HD 414) ensures very balanced sound;Lightweight: only 60 g without cable;Comfortable: headband with split padding;Rugged and durable: robust steel headband with metal joints, steel-reinforced headband ends, connection to the ear cups tested for durability.