Clarion SRV313 Features Dual voice coil 120 W high power amplifier with low pass filter Maxx Bass circuit for virtual bass enhancer 17cm counter drive woofer with dualneodymium magnet Air compression structure with aluminum die-cast enclosure Remote control for gain control /low pass filter (selectable 50/75/100/120 Hz)/phase select Blue LED power indicator RCA line level input/Speaker level input