products like an ecover generator software, or a pdf converter software, or a directory of publishers and on and on that make your main product more complete as a package. These are known as complementary products.
2) Supplementary OTO – Supplementary OTO are products that run inline with your main product / site theme. We use back the above example, assume that you are selling an ebook on how to write and publish ebook, therefore supplementary products that you can use in your OTO could be an upgraded version with Master Resale Rights to your ebook (that’s limited for 100 copies only) or maybe an upgrade to get your personal review of the first ebook your customer write etc. And one of the best examples would beHyperVre by Matt Callen. Upon sign up for the free software, you’ll then be directed to an OTO page for a GOLD membership upgrade at a low price that you’ll never get again. Yes, you read that right. “You’ll never get again”. Try to copy the OTO url and go back to that page after you’ve passed it. The page wouldn’t show. That’s a real OTO!