Metra 82-4300 1-Inch Universal Speaker Adapter Brackets Universal plastic spacer ring gives 1-Inch extra depth. Works with most 5.25-Inch, 6-Inch or 6.5-Inch speakers. Sold in pairs Dimensions: OD 6-5/8", ID 5-7/16 Universal plastic spacer ring gives 1" extra depth. Works with most 5-1/4", 6" or 6-1/2" speakers. Sold in pairs. Dimensions: OD 6-5/8", ID 5-7/16.