From MacPro(mid 2010) to iMac 27"-5K/Solution for desktop drives

Hello, I am completely new to this brand so I am a bit lost; where to start?

I am switching from a Mac Pro (mid 2010) to an iMac 27"-5K.
Apart from the system HD (Mac Pro) I have 3 more internal HD with my work (these are not backup drives) that I need now to use with the new iMac permanently.
HD´s are:

Toshiba Bulk X300 4TB
WD GREEN 3TB
WD RED 4TB

What G-Tech solution do you suggest, to accommodate this 3 drives (3 or more) connected to the new iMac 5K?
Thanks in advance for you kind help.
Regards.

Those are internal drives and new Macs don’t have the ability to add more internals. G-Tech doesn’t have a solution to help you with internal drives as we only make external storage and we don’t have empty enclosures to house those drives.

Hello Rydia, thank you for your explanation.
So, I can turn those 3 hard drives to backup drives but I need a desktop solution to expand and work with the iMac with about 12 TB of space. What G-Tech solution do you suggest?

We make a standard G-DRIVE w/ USB-C or TB3 with up to 12TB. We also make the G-RAID w/ TB3 that goes up to 24TB. It can then be configured as a RAID1 mirror device for 12TB of duplicated storage.

Thanks a lot; I will check those solutions.
Regards ,-)