OK for NAS DS923+
It's hard to find DDR4 ECC in SO-DIMM.
Synology memory is overpriced and this module works perfectly in 2x16GB on a DS923+.
No warning message saying that the product is not certified.
Faster than the standard 4GB PC-2666.
The verification test lasts a whole night, which is a long time but it's to make sure that it works.