For products deemed defective, returns can be made within 30 days of purchase (45 for international orders, to compensate for longer shipping times). If you need to return a product, contact me in order to confirm the nature of the defect, and a replacement cartridge will be shipped along with a prepaid mailer to return the defective cartridge.
Please note that I do not guarantee my products to work on clone systems (such as RetroDuo, SupaBoy, FC Twin, FC Mobile, etc), since compatibility can be spotty depending on the clone console. I only guarantee my products to work on original NES, SNES and Genesis hardware.
In addition, this replacement warranty does not cover the NES "blinking light" problem, as that is a symptom of a worn-out cartridge connector, and not an issue with the cartridge itself.
The only data I collect from you is what I need to fulfill orders, namely a billing and shipping address, and order transaction IDs for verification of payment. Your information will neither be sold nor given to any third party for any reason.