MODEL??	FBF57-4
DIMENSION??	57mm  x  10.5mm
VOICE COIL IMP??	8 ohm
SOUND PRESSVRE LEVEL?¡§S.P.L????	86 dB
RESONAT FREQUENEY??	380 Hz
EFFECTIVE FREQUENEY??	fo-15000 Hz
NOISE POWER??	0.5 w
MAGNET SIZE AND ASSEMBLY??	21mm Ferrite