I'm sorry about that I have a microwave the glass tray and a three prong gizmo that the glass tray sits on in my microwave three-pronged has a fitting down a hole in the bottom of the microwave which causes it to turn in a microwave the class cover sits on that three prong part, is supposed to turn with three-pronged and it doesn't all the time I'm wondering if there was a part missing that supposed to fit in between the glass and the three-part prong that make that turn.