These are a CNC molded 10” wheel side mount adapter with a 10.7” OD, 9” ID 5*, and a ½” mounting surface tilt to follow the flow more of the outside surface, to allow a deeper speaker to be mounted with enough room for proper ventilation. Max mounting depth will vary by size.
Using a Quality glue will achieve the best results. The inside diameter may have to be opened slightly as there are different speaker manufactures on the market. All new designs beginning 12/1/21 and material come with Speaker and ring mounting hardware. Threaded Inserts for speakers ( 8 ) 10-24 Stainless steel hardware, 16 stainless steel outer ring hardware. Drill bit and tool to put in inserts. Panel bond not included.