What exactly is "B stock"?


I'm looking at Denon DVD/CD players, and I keep coming across "B stock" merchandise. Would someone who is genuinely knowledgeable about this subject please give a clear, accurate definition of exactly what B stock is, and just how it differs from A stock? (Yes, I have a vague, generalized idea of the difference, but not one I'd want to take to the bank.) Thanks.
texasdave
I purchased a pair of B stock dynaudio special 25's that were used as the demo pair for Stereophile magazine. They are perfect in every way, I have a full set of measurements for my individual pair of speakers in the June 2005 stereophile, and Dynaudio has honored the full warranty and all other perks of buying "A" stock. Sometimes B stock can be very good buys.
I'm in the middle of a mess with an overseas seller that may be selling "B" stock as new. This is only speculation at this point because the seller is checking with the factory to determine if they made the modification. If we find that they in fact did not do it at the factory and it was not modified by either myself or the original buyer (I purchased on Agon from a very reliable and trustworthy source who did not even open the chassis.) This has the potential to be quite harmful to the credibility of this seller. So does the seller have a duty to disclose that a product was in fact a return, although it may be cosmetically perfect on the exterior?

Survey says ....
The above 2 responses are correct. I purchased a Yamaha DSP-A1 Integrated Amp/Processor 4 years ago as a "B" stock item, brand new. It has been a perfect piece of gear. I don't know why it was designated as such, as I could never find anything wrong with it. I do know this, I paid $650 for a $2799 piece of gear (it was the gold anodized unit with rosewood side-panels)and it had a standard Yamaha warranty except for "cosmetic" issues that might arise. I'd certainly do this again!
These days, it could mean anything except for new in box undamaged with valid warantee.