The Sony MDR-AS30G are behind-the-neck style headphones from Sony's Sports and Active Style line. The headphones feature Neodymium magnets which provide more power than the commonly used magnets for clear sound. They are very lightweight, at only 40 grams without the cord, and are designed with a unique stability tip which helps to hold the headphones in the ear and can flatten for portability. The MDR-AS30G have a 2 ft cord which makes it possible to use them with an arm-band as well as a 2 ft extension cord. The cord is single-sided with a gold-plated straight stereo plug. The headphones come with a hard carrying case and a cord clip. The MDR-AS50G differ from Sony's MDR-AS30G in their overall design. They are also heavier than the MDR-AS50G, have a smaller frequency range, and lack the moisture guard system which comes with the MDR-AS50G.