Quiklok BX718 Deluxe Bench w/ Extra-Thick 30x60cm SeatDeluxe keyboard bench with large extra thick seat cushion and durable, textured vinyl seat covering. The BX 718 bench uses a superior, heavy duty, unique height adjustment system with double steel rails and locking system with double steel rails and dual spring loaded pins on each leg for safe and secure height adjustments. Simply loosen lock screws, pinch together the spring loaded pins, slide leg to one of four height positions, pins snap into place