We require a good, rebuildable core to receive the refundable $225 core charge back. Please remove your pit-man arm before sending your box to us. We recommend using a USPS Priority Flat Rate box as shipping to us will be under $20 from all 50 states. When returning a core please include a copy of your invoice. Keep in mind if you are returning your core to us after 30 days has passed you will get your refund in the form of an in-store credit.