Universal 1" Plastic Depth Ring Adapter/ Spacer for S/2 5.25 "- 6" Car Speakers Universal 1-inch Plastic Spacer Rings for 5.25-inch and 6-inch Round Speakers Inner Depth: 5-1/8" Made From ABS Plastic 1-inch Allows Extra Mounting Depth Fits most 5.25 inch - 6.5 inch Speakers | Oversized 6.5" speakers will not work with these spacers