In the story of the person who set it up, the product was hard and it was hard to open. It seems that it seems to be hard to winter because it seems that it has finally opened after warming with hot water. And it seems that it was not closed after fixing the main body screw. It seems that it was useless even if using lubricant or hitting with a 2 pound hammer. After all, I made a hole with a hole saw on the front side of the main body, and fixed the screw in a closed state. I think that it is inexpensive and the strength of the product itself seems to be high, so I would like to revenge in warm time.