| Operation Steps：
1. Prepare the glass lid and check the dynamometer, slider, fixed trestle.
2. Install the knob appropriate test endshield to the glass lid, mount the screw and put it on the test platform and fix it.
3. Connect the hook of the dynamometer with the bolt of the endshield, rotate the block adjuster.
4. After test, Check the glass lid if there is broken or crack near the knob hole. No broken or crack is qualified.