https://wccftech.com/ekwb-announces-str4-velocity-water-blocks-with-support-for-3rd-gen-ryzen-threadripper-cpus/

EK announced the Velocity sTR4 series water blocks that are specifically designed for HEDT AMD Ryzen Threadripper processors are compatible with all newly released AMD TRX40 based motherboards equipped with socket sTRX4  which supports Ryzen Threadripper 3000 Series Processors.

With the release of 32 core count HEDT computer processors and potential for even more cores, the requirement for the top of the line cooling has never been bigger. The sTR4 Lineup of EK-Velocity water blocks, designed for the sTR4 socket, is perfectly compatible with the newly released AMD TRX40 motherboards that are using the sTRX4 socket. The only difference between the sTR4 and sTRX40 sockets is the pin layout, thus it has no effect on the cooling performance or the mounting itself.