Overall a good product, the kit was missing a second seal ring and it would not begin vacuum . . not sealing. The Customer Service was persistent in understanding English to know what was needed. I imagine they were as frustrated as me, but stuck with the process and after a slow boat, I got the part. The interaction was clunky, but they did not hesitate. The vacuum pump pulled within a faction of the actual barometer and the valves and hoses sealed. It held a constant vacuum for more than 24 hrs. In my experience that is tough to attain. Even with the delay to put in service - it is RECOMMENDED. The best part is it has a thick GLASS cover. It is stiff and durable, and by far the best attribute of this product and alone worth the price.