Hertz SV 165.1 6.5" 400 Watts Midrange Speakers Size: mm (in.) 165 (6.5) | Power Handling: Peak W 400 Impedance:  4 | Frequency response: Hz 100  10k Sensitivity: dB SPL 97 | Voice coil:  mm (in.) 38 (1.5) Magnet High density flux ferrite | Cone/Dome Ultra light pressed paper