Strong cold punching iron mesh, not easy to deform Good sound transmission, no sound and sound interference Carefully designed to provide full protection for the horn, moisture and impact Resistance to fading and atmospheric pollution product information: Product name: Speaker grille Surface treatment: spray paint Colour:Black Material:Cold rolled steel + ABS Size: 4inch Size:Outer ring diameter: 124mm, inner ring diameter: 94mm Package Contents: 8 x Speaker grille Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.