Infinity PRIMUS250BK (Ea) Primus 250 Black 2 Way Speaker with MMD Drivers Frequency Response (3dB): 49Hz - 20kHz Recommended Amplifier Range: 10 - 150 Watts High-Frequency Driver: 3/4" (19mm) MMD Dim: 35-1/2 X 7-3/8 X 11-3/4 Inches