BokWin 2 Pcs Universal Fit Car Speaker Spacer 4 Inch Adaptor Ring Mounting Bracket Plastic Car Stereo Speakers Spacer(Black) Features: 1.High quality plastic, durable and wearable. 2.Suitable for cars, boats, trucks, RVs, etc.Replacement speakers can be installed into the original openings of the car audio system. Specification: Material: plastic. Outside Diameter:5.31"/135mm Inner Diameter:3.93"/100mm Color: Black Package contains: 2 x Car Stereo Speakers Spacer Notices 1.Since the size is manually measured, please allow an error of 1-2mm 2.The color of the product may vary slightly due to photography & your screen