SOUND TOWN ZS-V1812X2OC: This ZETHUS line array set includes (2) ZETHUS-112B passive line array speakers, (1) ZETHUS-VX118S passive line array subwoofer, and (1) ZSCB-VX18S caster board ZETHUS-112B FULL-RANGE SPEAKERS: Each ZETHUS-112B passive line array speaker features a 12 woofer and two 1.4 titanium compression drivers, delivering 400W RMS, 800W program power (8) handling capability and a full-range or bi-amp switch ZETHUS-VX118S SUBWOOFER: The ZETHUS-VX118S passive line array subwoofer features a powerful 18 woofer delivering 800W RMS, 1600W program power (8) handling capability. Includes the ZSCB-VX18S caster board for hassle-free transportation (supports up to 660 lbs.)