The Vault FW6 series supports an internal 2.5 SSD which can be mounted to the bottom plate and connects to the motherboard with a SATA power cable
Universal SSD Cloning and Transfer Kit (USB 3.0 to SATA) –
SATA Mount and cable kit for Odroid M1 – iCode
Ssd Mounting Bracket 2.5 To Ssd Mounting Kit With Sata Cable - Temu
Molex 4 Pin to x2 15 Pin SATA Power Splitter Cable and x2 SATA Cables (Data) included Screw pack included to mount the drives Quick and easy
SABRENT 3.5 Inch to x2 SSD / 2.5 Inch Internal Hard Drive Mounting Kit [SATA and Power Cables Included] (BK-HDCC)
Orico USB 3.0 to SATA HDD and SSD Adapter Cable Converter - 2.5 inch SATA drives - 5Gbps, SATA I, II and III - Orico
Helpful SSD Accessories
Upgrade Your Mac Mini A1347 Server SSD With Bottom Hard Disc Drive HDD Flex Cable Kit 821 1500 A 2011 2013 And Oscillating Tool From Sun3flower, $4.23
2.5 to 3.5 SSD Hard Drive Adapter Metal Mounting Bracket Converter w/ 18 SATA Data Cable and 6“ Molex 4-pin to SATA 15-pin Power Cable Combo Kit
Ssd Mounting Bracket 2.5 To Ssd Mounting Kit With Sata Cable - Temu
One stop shop for USB serial adapter, VGA M/M cable, OTG, MHL , USB 3.0, HDMI, DSL Filter, Augmented Cat6A cable, all lengths all color networking
2.5in SSD/Hard Drive Installation Kit For Two (2) 2.5” SSD/HDD to 3.5” Drive Bay with SATA Data and Power Cables