The SONY MDR-CD900ST is a dynamic stereo headphone ideal for digital audio. - Brand: SONY - Model: MDR-CD900ST - Type: Dynamic Stereo Headphones - Application: For digital use I'm selling these because I haven't used them much in the past few years, as they didn't quite fit my ears. The ear pads have deteriorated, so I've removed them. There are no particular problems with the output, etc., but there are some scratches and signs of use.