1.5" Driver for Budget Projects Unique patented Design 113 dB sensitivity 1 W / 1 m 1 kHz Crossover Extended high frequency response up to 20 kHz Very small Size and low Weight 44.4 mm Voice Coil BMS 4555 is a powerful 1.5" professional compression driver that delivers outstanding sonic quality in a small package. The BMS exclusive voice coil technology employs a light weight Copper Clad Aluminium wire wound inside and outside of the Kapton? former to improve the heat dissipation, dramatically increasing the acoustic output and reliability of the driver while minimising the power compression. The BMS 4555 - 1" compression driver is designed for a wide variety of applications including budget projects requiring 1.5" driver of high sonic quality. The 4555 offers all the benefits of the patented BMS compression driver in a 1.5" format, but at much reduced cost.