Specification: Frame Material: ABS Plastic Mesh Material: Cold Rolled Steel Outer Diameter: 66mm / 2.6 inch Inner Diameter: 46mm / 1.81 inch Screw Hole Diameter: 3mm / 0.12 inch Diagonal Center Hole Distance: 57mm / 2.24 inch Package Content: 4pcs x Speaker Grill with Screws Description: Distribute screws, make you more convenient installation. Great for speaker cabinet, home speaker or speaker. Protect your Subwoofer from cuts, rips, tears and dents.