Material: Plastic + Cold Rolled Steel Frame and Mesh Color: Black Size: 108x108mm/4.25"x4.25" Inner Diameter: 90mm/3.54" Diagonal Center Hole Distance: 113mm/4.45" Specification:Note: The speaker cover is used for 4inch inch speaker,but not suitable for each 4inch inch speaker.Please see the detailed dimensions carefully and confirm whether applicable to your speaker before placing orders. Due to manual measurement,please allow 0.5-3mm deviation Frame Material: Plastic Mesh Material: Cold Rolled Steel Frame and Mesh Color: Black Size: 108x108mm/4.25inchx4.25inch Inner Diameter: 90mm/3.54inch Diagonal Center Hole Distance: 113mm/4.45inch Adjacent Center Hole Distance: 76.4mm/3.01inch Height: 16mm/0.63inch Error: ±3mm/0.12inch Package Included: Speaker Cover x 2