SOUND TOWN ZETHUS ZSCB-215S CASTER BOARD: Safely transport your Sound Town ZETHUS-215S/215SPW subwoofers (sold separately) or utilize them as a mobile ground stack set up DURABLE AND RELIABLE: Built with a high-quality plywood material, providing reliable strength and longevity. Supports a maximum weight of 660 lbs NOISE-FREE ROLLING: With polyurethane rubber, the caster makes movement easy and noiseless. Two casters are equipped with locking brakes SUBWOOFER ADAPTER: Featuring a two-slotted design on the board for better subwoofer adaptation to securely mobilize your setup during events CONVENIENT HANDLES: Two convenient handle openings for easy carrying and storage