Aguilar OBP-3SK/PP Onboard Preamp<div style="text-align: left;"><strong>[Product Information]</strong><ul><li><span class="a-list-item"> Includes stacked Treble/Bass pot and separateMid pot. Mid pot is push/pull for Midrange frequency selection </span></li><li><span class="a-list-item"> plus/minus 18dB bass at 40Hz </span></li><li><span class="a-list-item"> plus/minus 16 db of cut and boost at either 400Hz or 800 Hz </span></li><li><span class="a-list-item"> plus/minus 16 dB @ 6.5KHz </span></li><li><span class="a-list-item"> Battery life: 324 hours </span></li></ul></div><img src="http://ecx.images-amazon.com/images/I/318oWXU1RKL.jpg" noproxy>