Because it was low price, I was worried about the quality, but it was no problem at all, rather it was more than I expected. I bought it for use as a tennis ball pressurizer ball in / out part, but the O ring is also thick, it is enough without air leakage.
It withstands the pressure of the well pump and withstands even a high temperature of 60 degrees or more. I am worried about how durable it is because it is different from normal usage. I think that there is considerable durability if it is usual usage method because it is so good that it can be used for home made solar water heater. Depending on the idea, it is likely to be used in various ways.