Often times we see initials used in Ebay titles and descriptions when describing Vintage TOYS and DOLLS. This is what they mean:
MIB: 'Mint in Box' means this item is in MINT condition and in its original box.
NIB: 'New in the Box' means the item looks the way it did when it came from the factory, and more than likely never played with.
NRFB: 'Never Removed From the Box' means the item has never been taken out of the original box, thus never handled.
NOS: 'New Old Stock' generally refers to a 'lot' or 'bulk' items that have been discovered tucked away from an old store or business. Generally these items are in their original packaging which generally has 'shelf dust,' but the actual item has been protected.
MIBS: There is NO such initial description as MIBS when referring to antiques and collectibles. MIBS is a error/mistake that obviously was made while someone was listing on Ebay. Actually the correct term is MIB, not MISB. So often sellers copy/follow others when listing, and the mistake has been repeated. To be a knowledgeable seller, use the term MIB, not MIBS. If the box has a cellophane wrapper, and it has not been removed, sometimes the letters MISB are used, which means Mint in Sealed Box.
Hopefully this has shed some light on some of the 'mystery' initials used on Ebay and other sites. If this has been helpful, please vote YES. Thank you.