Rockville (4) RM84PRO 8" 4 Ohm 1200 Watt SPL Midrange/Mid-Bass Car Speakers Rockville RM84PRO 8 Open Basket Midrange Speaker. Power Rating: 300 Watts Peak /150 Watts RMS, CEA Compliant Power Ratings Kevlar Reinforced Black Pulp Cone. Treated Cloth Accordion Suspension, Linear Progressive Conex Spider Kevlar Reinforced Pulp Paper Dustcap. High Tensile Expanded Steel Basket, Oversize 1.5 High Temperature CCAR Voice Coil. 100oz. Magnet Structure Weight Impedance: 4-Ohm. Mounting Depth: 3.46, Frequency Response: 88Hz - 6KHz Sensitivity: 108dB @ 1w / 1m. Cutout diameter: 7.25", Mounting hole diameter: 4 holes- 0.197" x 0.276" (4) Rockville RM84PRO 8&#034; Car Speakers Totaling 1200 Watts Rockville RM84PRO 8 Open Basket Midrange Speaker Power Rating: 300 Watts Peak /150 Watts RMS CEA Compliant Power Ratings Kevlar Reinforced Black Pulp Cone Treated Cloth Accordion Suspension Linear Progressive Conex Spider Kevlar Reinforced Pulp Paper Dustcap High Tensile Expanded Steel Basket Oversize 1.5 High Temperature CCAR Voice Coil 100oz. Magnet Structure Weight Impedance: 4-Ohm Mounting Depth: 3.46 Frequency Response: 88Hz - 6KHz Sensitivity: 108dB @ 1w / 1m Cutout diameter: 7.25 Mounting hole diameter: 4 holes- 0.197&#034; x 0.276&#034; REVC: 3.600 Ohm FO: 88.896 Hz SD: 226.980sqCM BL: 4.827 T QMS: 3.176 QES: 0.585 QTS: 0.494 NO: 4.017 % SPL: 108 dB VAS: 34.598 Ltr CMS: 472.917u M/N KRM: 3.644m Ohm ERM: 0.708 MMS: 6.778 g MMD: 4.812m Kg KXM: 20.572m Ohm EXM: 0.554