A simple bracket for mounting a 2.5" HDD to something (e.g. a piece of plywood). The bracket mounts using normal HDD screws to the back of the hard drive. Usually, these screws are rather short, that's why the bracket is also quite thin. However, it should be able to withstand normal "stationary" usage. The bracket then mounts to something else using 3mm thick screws (e.g. a piece of plywood, cabinet doors, etc.).

Also note that the spacing of screws on hard drives is quite precise, so the printer and material need to be quite dimensionally precise, otherwise the holes will not fit the drive. But as always with plastic, there is a bit of wiggle room, so it should not be a big deal.

(IRL photos will be added shortly, I'm don't have access to the computer which uses the bracket right now)