1. The metal shell of the electric wrench should be reliably grounded, and its shell should be performed for a regular inspection test and within the validity period.
2. Check the tightening of the screws of the electric phone body. If the screw is found, it should be tightened immediately, otherwise it will cause the electric wrench to fail.
3. Check that the handle of the handheld electric wound is intact, it can be damaged without cracking, and the installation is firm.
