Questions about Icy Dock Removable frame 2.5" MB324SP-B

Are the four frames/trays included or do you have to buy them?

Hello all. I wanted to ask if and where there is such a removable frame for 3.5 inch hard drives? I can't find anything here. If possible, it should have room for 5 hard drives or more and not cost 1 million. It would be cool if hot swapping was supported and 3.5 AND 2.5 inch disks could go in. But especially 3.5 inch. I need that for a self-built pc case. Thanks for the effort and have a nice sunday :)