1. 2. A tuned port designed for bass drum 3. Extend your low-end frequencies 4. Add more punch to your sound 5. Make the bass part more powerful, and the effect is adjustable; adjust the tightness of the drum surface to customize the response Enhancer instantly improves the sound of any bass drum High wear-resistant and excellent durability Usage: First place the protective sticker on the kick drum skin and cut along the inner diameter circle to form a complete circle. Attach the rubber part of the enhancer to the drum skin; installation is complete Color: White Material: ABS + Rubber Size: Outer diameter: 18.5 cm Inner diameter: 10.6 cm (4.17 inches) Height: 10.5 cm (4.13 inches) Weight: 190 g (6.7 oz) Package Contents: 1 x Bass Drum Enhancer 1 x Protection Sticker Note: The package includes only the items listed above. Other accessories are not included. Lighting and display differences may cause slight variations in color between the image and the actual item. Measurement error allowance: +/- 1-3 cm