18-inch subwoofer speaker. 2-inch voice coil, 50oz magnet. Durable black carpet cover. Heavy-duty plastic protective corners. Integrated recessed carrying handles for easy handling. Binding post (banana jack) and two 1/4-inch (6.3mm) jack inputs for easy daisy-chaining. Base mount inserts for mounting on speaker stands. 97dB sensitivity. Optional SMP-3 speaker mounting pole available.