CL14 Model F4-3000C14D-32GTZ to be exact. Bought them in March of 2017 (for only $439 combined) when I heard memory prices would be going up for my Ryzen 1700 build. Ever since the Agesa 1.0.0.6 bios updates I have been able to run all 4 for a total of 64 GB with its XMP profile of CL14-14-14-34-48 T1 with no issues on an Asrock X370 Fatal1ty Pro Gaming mobo. It could probably run higher with looser timings, but I don't see much benefit in that... I did try 3200 for a bit, but I didn't feel like playing with the memory timings after I had a couple of reboots with the CL14 timings @ 3200.

Moral of the story, don't pay more for "Specialty branded for your CPU" memory. It is just a gimmick to make you pay more.

Don't be a fool... I bought 2 sets of Trident Z 2x16GB 3000s with