Check the listing for details. BBM466A20 *REMANUFACTURED* amp with core return REFUND Mazda BOSE. Condition: Used. Listed at 249.99 USD. BBM466A20 *REMANUFACTURED* amp with core return REFUND Mazda BOSE. Condition is Seller refurbished. This unit has been remanufactured and has the latest firmware to resolve a few known issues. The listing comes with the opportunity of returning your defective core amplifier for a $50 refund. Core refund process: We provide a return shipping label in the box with the unit that you have purchased.You return your old/defective core in the same packaging using the enclosed return shipping label.We process a refund to your transaction method within 3 business days of receipt and you'll be notified via eBay that a refund has been processed.Most units qualify for the full refund amount, though major liquid and physical damage can lower the refund amount. Please reach out with any questions. We’re more than happy to assist with questions related to the issues that you are experiencing with your audio system.