“Read the fine print. Although the write-up states that it fits on a Zip Navigator (the fine print; that I didn’t notice, states that it doesn’t fit on a Zip Navigator AT. The customer service rep said that MGI does not make the part for the AT model. The cost to ship the part is about the same as the cost of the part. To get a refund, I needed to ship the part back at my expense. I just threw it away.”