It's a no-fuss vinyl amplifier/RIAA amplifier for systems made before the re-emerging of vinyl as a viable media(IE, 2000-2015 or so).
It does the job perfectly, no hum, no hiss(other than already present from the vinyl), it just works, and is quite unobtrusive, if you decide to have it visible.
I haven't used the headphone jack, since I'm using it for a stereo system, but I can't imagine anything other, than that this works perfectly fine as well.
Granted, this isn't audiophile level snobbery gear, but it's perfect for anyone that just wants to play their vinyls on a system that doesn't come with some kind of RIAA amplifier already built in.
Overall, well worth the money.