I have found a seller that has the Samsung 840 PRO 256GB with two different mfr number (MZ-7PD256BW and MZ-7PD256Z):
Does somebody know what the difference is? I asked the seller but I have not had an answer yet.
After a small amount of checking it appears that the "Z" is a bulk package and the "BW" is a commercial complete package but that is a quick opinion of mine based on 2 minutes of googling. Check with the vendor.
Crucial has a similarly byzantine nomenclature. Their models numbers have codes like SD1 and SD2, followed by things like CCA and BAA. From all appearances, the specs are identical.
Thanks for taking the time to answer, the vendor response is:
“It looks like MZ-7PD256B is the Basic Retail Version, but it doesn’t come with a mounting kit.
The MZ-7PD256Z is the Bulk Version.”