This Is A Brand New Aftermarket Replacement Diaphragm 8ohm For Samson S15HD S215HD High Frequency Horn Driver Overall Diaphragm Diameter: 3.15" (80mm) Voice Coil Diameter: 1. 35" (34mm) Mounting Holes: 2.87" (72.9mm) Center To Center Nominal Impedance: 8 ohms