Used original Roland motherboard ASSY, MAIN BOARD RS-540Number: 6700989010Compatible models: Roland RS-540 The board needs to be installed under the guidance of professionals. (The new motherboard is an empty board, and professionals are required to install the firmware and program parameters)2: Due to the nature of equipment parts and many factors of installation, our company does not accept returns. Please refuse delivery if there is any visible damage to the packaging.3: It is best to contact me before purchasing, and I will professionally analyze and judge the fault before shooting. Some areas can support door-to-door installation, and negotiate to charge door-to-door fees, please consult customer service for details.4: Once the accessories are installed on the machine, our company does not accept any returns and refunds.