Loosen the lower element on a electric water heater
I believe the tool you are using is a plumbers socket. It is usually sized at 1 1/8th inch. The reason the heating element isn't removing easily is probably due to hard water build up on its threads. What I do when I encounter a stubborn heating element is to apply extra leverage to the socket. If you can supplement a cheater bar with the socket handle the element should unscrew with no effort. A 1/2 inch diameter steel pipe fitted over the handle will work. Or any object that will extend the socket handle several inches will also suffice.