Pros: Cheap 4x2.5" bay. This is all you need to organize some solid state drive for use in an array. Fast pass-through sata speeds, virtual zero loss. Power and activity lights.

Cons: Cheap, even though that is also a positive, 5.25" bay tolerance is sometimes exceeded by poor sheet metal cutting creating interference when installing. Purchased two, issue existed with only one, installed with significant force. Fan silent at first, however very loud after a few minutes. Cheap 40mm x 10mm fan that is unsecured in the unit, sound is likely generated from blades being pushed against the interface card. Plastic base and threads, caution if taking unit apart. Plastic trays, caution when inserting and ejecting, use minimal force. Lower 5.25" bay screws do interfere with lower trays when using tall hdds (12mm) suggest not using those two screws.

Overall Review: Note: some people have stated that the 40mm fan can not be replaced, this is completely inaccurate, the fan can be removed properly and replaced with any 40mm x 10mm fan. Issue however, is that it will remain unsecured (unless screwing into the plastic backing) which will almost always result in some vibratory noise. If removing the fan, caution should be exercised when removing the upper IC as there is a power riser interconnecting the two ICs. Also, lower IC is connected to all power LED light and can not be fully removed but tilted to allow access to the 2 pin fan connection. Trays would be strongly recommended for SSD installations which require no additional ventilation. Standard HDDs consider another tray, or replacing the fan immediately. People that are doing large number of insertions, should not purchase this tray, honestly it is not meant for that type of use, this is a chassis for holding hdds, not for enterprise hot swap usage. Tray connection is combined SATA power and data, rather than SFF-8482 (SAS/SATA), this tray does not support SAS drives. There are lots of trays out there, make sure this suits your needs. Personally, perfect for my SSD home server setup as all other 3.5" bays are used for large TB drives.