Fiio K9 PRO ESS Headphone Amplifier DAC This is a domestic genuine product. I have used it for about 2 hours, 1-2 times every two weeks since I purchased it. Usage is infrequent, and since it's a stationary type, it's in a clean condition with little sign of use. Please check the condition of the product in the photos. I liked the sound quality very much, but I am selling it to someone who needs it because I purchased another device. It is also being sold elsewhere, so it may be sold out. It will be first-come, first-served, so please understand.