This guy. It sold for around $60 when I bought it. Similar products pop up for around that price regularly, if you keep an eye out on Amazon. The prices seem to vary dramatically. You could also do something like this https://www.amazon.com/dp/B01M0BIPYC/ref=cm_sw_r_cp_api_i_scKfDbAZ91ST8. Just search Amazon for 'hot swap cage' and you'll see plenty.

This was my first ever build of a pc of any kind. My wife bought me a Synology last Christmas, and I quickly became addicted to Data hoarding, among other projects. So, I started out on a journey to build a cheap, rack-mount, unRAID server with my kids. That plan quickly morphed into the RGB filled beast you see now, but I couldn’t be happier with it!

Edit: Full Spec list

Case: Fractal Define 7 XL w/ light tempered glass

MoBo: Asrock Fatal1ty X399 Prpfessional Gaming

CPU: 24 core Threadripper 2970wx

GPU: EVGA GeForce GTX 1080 to FTW3 11GB

2nd GPU: MSI Radeon RX 580 Gaming 4G

RAM: 64GBG.Skill Trident Z RGB)

Storage:

3 x 512GB Samsung SM951 m.2 NVME drives for VMs and Docker.

2 x 14TB Seagate Exos x16 as parity disk

6 x 8TB Seagate Exos 7E8 plus 2 x 10 TB Seagate IronWolf as main volume.

6 x 1TB Seagate IronWolf 125 SSDs in an Icy Dock 6 x 2.5 SSD hot swap cage in the second 5.25 drive bay, as second cache pool for plex, downloads, and everything else.

Optical drive: ASUS BW-16D1HT from Cloner Alliance.

Cooling:

360mm NZXT Kraken Z73

4 x Deepcool RF120m RGB fans.

4 x Coolermaster MF 140R Fans