Some delay with the payment and acceptance on Treatstock, yet the hub turned out to accept the payment as done and started printing right away. In GreenTec Pro the print turned out near perfect. Firm, neat, and without cracks.
I looked for a print hub that could do 3D printing with TPU/TPE. The hub reacted fast and accurate, and produced within two days. The result as can be seen is a flexPLA print, which is much less flexible and more brittle thanTPU/TPE. The caps fit almost perfect, but several broke while dismounting. I mentioned the use of flexPLA instead of the options as stated by treatstock. The hub responded revealing a technical aspect of the production proces: the fact that the printer in use can not print TPU/TPE. The mounted caps deserve a precosious handling and will propably do fine while in use.