This is to replace the feet on your Creality CR-10 or CR-10S (I assume the frame mounts are the same-- I use it on my CR-10S). In theory, these should make your printer a little quieter than the stock feet (though I didn't test the noise before and after). It's an alternative to the squash ball feet that are pretty popular.
The feet are 2cm tall when unloaded, and squish down to around 1.7cm when the weight of the printer is on them. The dome shape allows the TPU to act as a soft spring to prevent transferring vibrations.
Version 2 has been recreated in Fusion 360, and now comes in 3 different thicknesses, so you can choose your firmness to meet your filament and weight needs. 1.8mm is almost identical to version 1, but 2.4mm and 2.8mm thickness will be significantly more sturdy.
CCTREE TPU has a shore hardness between 90 and 98. 1.8mm thickness is designed with that harness in mind. If you have a softer TPU/TPE, you might need to use the other thicknesses.