Specification: Frame Material: ABS Plastic Mesh Material: Cold Rolled Steel Outer Diameter: 185mm / 7.28 inch Inner Diameter: 146mm / 5.75 inch Screw Hole Diameter: 4mm / 0.16 inch Diagonal Center Hole Distance: 167mm / 6.5 inch Package Content: 1 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. NOTE:Please measure the diagonal distance of the speaker mounting hole before purchasing.