For used products with manufacturer defects we offer a full 1 year warranty from the date of purchase. This warranty applies to the product under normal use and is subject to all product usage documentation. In the event you need to exchange your battery or charger, simply complete the Return Merchandise Authorization (RMA) form, place the RMA form, a proof-of-purchase, and the item(s) to be exchanged in an appropriate envelope, and mail it to us at the address indicated on the RMA form. RMA forms can be obtained by emailing or calling customer service. Please allow 1-3 days for processing. NOTE: All exchange requests MUST be accompanied by an RMA form, a proof-of-purchase, and all items to be exchanged. This request must be received within 30 days from the original purchase date. We reserve the right to refuse any exchange request that does not meet these requirements. We recommend that you return your product via traceable mail as we do not take any responsibility for undelivered exchanges. Cannastick.com is not responsible for reimbursing any shipping fees incurred when returning exchanges. All exchange requests MUST be accompanied by a proof-of-purchase. Any package received without a proof-of-purchase will be returned to the sender. We reserve the right to refuse any exchange request that does not meet these requirements.