Many ring sellers on eBay are not professionals. (Even professionals might pretend not to know specifications about rings they auction). Some don't have devices to measure the size of a ring they want to auction or sell. Here's a tip for determining a good approximate ring size:
If a dime passes thru the ring opening tightly, the ring is a 7.5.
If a penny passes thru the ring opening tightly, the ring is a 9.5.
If a nickle passes thru the ring opening tightly, the ring is an 11.5.
There are also approximations. If a dime, for instance, passes thru loosely, but a penny won't go thru, estimate that the ring is around an 8-9.
Many sellers who don't usually sell rings have found this tip useful. But even more buyers have! As buyers of rookie ring sellers (as well as pros who don't bother writing detailed item descriptions), we don't get enough information in the seller's item description to know if we want the ring. Knowing the size is crucial to most ring buyers.
If a buyer doesn't advertise the ring's size, ask them (from eBay's message portal), "does a dime, penny or nickle pass through the opening?" Once they respond, you'll have a very good idea about what is the size of the ring they are offering. Plus, since you've sent it via eBay's website you'll have an official record of the seller's response just in case the ring doesn't match the information provided.
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