Reman Alternator. Warranty Duration. Obviously, the core won't be working well (or you wouldn't have replaced it) but it can't be smashed, rusted solid, or otherwise unusable. (We rarely reject a core. ).
I bought this one to replace my two year old one on my 86 Fiero. For some reason my old Fiero is pretty tough on alternators. I only get a few years out of one. I've had new and rebuilt ones and both types last about the same. So far this one is working fine and the price was reasonable.