This is a wireless headset that provides 7.1-channel sound with a digital surround headphone system. - Brand: SONY - Model Name: MDR-DS7500 - Type: Wireless Headset - Features: Digital Surround Headphone System - Connection Type: HDMI - Surround System: 7.1 Channel - Supported Audio Formats: Dolby Digital, DTS-HD I purchased this at an electronics retailer for around ¥55,000. I haven't had a chance to use it, so it has been stored unopened at home. I took it out of the box for the photos, but I haven't touched the headphones themselves directly. There are no noticeable scratches or damage, but due to personal storage, there is some exterior damage to the outer box, such as scratches and corner wear. The main unit and instruction manual are unused and new. I opened them for the photos. Other than that, there are no major defects to note, but please refrain from purchasing if you are sensitive to minor imperfections or are looking for a completely new item. There is some age-related deterioration from personal storage. Please consider this before purchasing. This item was personally owned and stored at home. I am selling it at a lower price than the list price as part of a decluttering effort. I will take the utmost care in packaging and shipping. Therefore, I kindly ask that you purchase this item only if you agree to a no-claims, no-returns transaction. This product is currently discontinued, but it was very popular, so if you were looking for one, please consider purchasing it at this opportunity. #SONY #MDRDS7500 #WirelessHeadset #DigitalSurroundHeadphoneSystem #Headphones