About this 3D model

My prior model had a small rounded top. I have since moved to a flat disc shape on both sides, which I like better for gripping the spinner. Here are two options, with thin and medium thickness. Note: This is for an 8x22x7 bearing, standard skateboard bearing. Note 2: The .STL file called BearingCenterpiece8mm.STL is a tighter fit for the cap.