10" powered subwoofer. Nice analog design. Black ash cabinet (vinyl 18" x 16"). Vented at front. Ribbed paper cone / rubber surround. Phase switch 0 or 180 degrees. Adjustable variable crossover frequency 50-150 Hz. Level control. Low level inputs R & L. Speaker level inputs. High level outputs. Modified filter for better subsonic equalization. Dampened cabinet for lower bass. Very low use. Mission logo missing on grill. Grill has (2) small pull / hole on bottom edge. Condition 9