What are the characteristics of a check valve?

I don’t know any specifics, because the https://www.pomwaterproofing.ca/back...-installation/ team helped me in this matter. But I can tell you for sure that it’s definitely not worth saving on the cost of the valve itself, otherwise it will turn out to be a story, like my friend, who paid twice. The miser always pays twice, you should remember this. It’s better now to look at the options for work on the website of this company and contact people who really understand this.