Thanks for clarifying. Also, does the brand of converter matter or are they all pretty much the same? I was going to get either some off-brand Chinese product or one from OWC. Normally I would go for the OWC product but they aren’t in stock right now. Does the quality of the connection on the converter affect the performance of the ssd, or is this not a factor? I just don’t want any issues once I install the ssd.
I don't think the make should be too much of an issue, although the old maxim of you get what you pay for is probably worth bearing in mind. Just as a possible suggestion, the following link is the Amazon recommended product on their US site:

DY-tech 2nd Hard Drive HDD SSD Caddy for iMac 20 21.5 27 inch 2009 2010 2011 Early Late
1. The 2nd Hard Disk Drive Caddy / Adapter to bring you new maximum data storage flexibility, with the compact portable design. Which works with 2.5" inch 12.5mm / 9.5mm / 7mm Serial ATA Hard drive HDD and SSD (Solid State Drive) as well. With the second HDD/SSD in your Laptop, You can speed to...
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