Suitable for speakers: no more than 2 inches in height for tweeters, no more than 4 inches for mid-range. The central hole is divided into two sections. Install a 4-inch midrange speaker, then remove the washer to install a 100mm diameter 4-inch midrange speaker. Install a 3-inch or 3.5-inch midrange and use the washer on the pad. (When installing a 3.5-inch midrange speaker with aperture and speaker cover, ensure the car column is larger than 111mm.) Tweeter outer diameter: 58mm. Tweeter inner diameter: 47mm. Mid-range outer diameter: 102mm. Mid-range inner diameter: 85mm. Maximum bracket width: 111mm. Bracket length: 270mm. Color: White. Material: Plastic. Package contents: 4 speaker brackets. Only the items listed are included; other products are not included. Note: Lighting and display differences may cause slight variations in color between the image and the actual item. Measurement error allowance: +/- 1-3cm.