Was able to install Had Drives in each sled with ease and NO TOOLS!
I put 2 - 1TB with a computer software raid setup along with the other 2 - 2TB HD's also with ease. I plan to get a second one later to put my 4TB HD's into so tyo free up a couple of my USB 3 single drive sled with fan. This is a great working little hard drive stack.
I was amazed at how simple this device was to set up and to use. The kit includes all the screws; but, since I use 3.5" hard drives I just snapped the drives in place. Since I had used external enclosures for some of my drives they already had drive letters assigned. Therefore I didn't have to do anything. For the others Windows 10 recognized them and stepped me through the set up process. Now their use is transparent. It couldn't be easier.