While oogling assorted NVMe gear, I ran across a bit of an oddball device. U.2 2.5" form factor device that hosts a PCIe switch and 4 M.2 22110 drives. An interesting potential alternative to an Amfeltec Squid.
Viking Enterprise Solutions
U.2 NVMe SSD M.2 Carrier High Performance Solid...
Previously it was reported that the Viking Technology U.2 NVMe NVRAM drive was no longer available despite only a year after announcement, or at the least no ordinary humans could obtain it.
VT-PM8 & VT-PM16 Persistent Memory Drive - Viking Technology | Memory and Storage Solutions