The Fosi Audio ZA3 is a digital integrated amplifier. It's small and easy to use, and I bought it for a sub-system, but I'm selling it because I've decided not to build the sub-system. I used it for about 10 hours, so it's not heavily used, but there were no problems with its operation. I will ship it in its original box. - Brand: Fosi Audio - Model Name: ZA3 - Included Accessories: Power adapter, User manual