Very fast and professional contact using the alibaba messenger with Carol from the company. I never ordered a tank like this before and she explained everything in good englisch and very clear. We discussed different positions of the tank valves and the dimensions, to find the optimal solutions for my case. Very good. It took only 2 weeks after my order to produce the tanks with my individuell dimensions, until the tanks arrived at my adress in germany. Product quality also is nice :-)