When you create or edit a text link (image or flash) banner, there is a possibility to define a SEO string parameter. This is very useful if you want to increase your search engine ranking for html text links placed on the web. Usually, if you use html links with affiliate parameters, this might lower your rating in the search engine ratings. If you would use an iframe wrapper, you can append the SEO string after the link without affiliate parameters in the noscript part of the iframe banner code. Read more here about iframe wrapper (advantage - the code on the web site generates a link, so if you change the link in the merchant panel, you don't need to change the code on the web site).
After you create a text link banner with the SEO string parameter, go to configuration - banners & links formats. There, you would need to change the iframe banner wrapper. In the editor on the right side, put the seostring variable to the noscript part of the iframe (from the list of variables). Do not forget to save the changed iframe wrapper.
Affiliate would be able to get the banner code in his affiliate panel. If the customer of the visitor of the web site holds the mouse cursor over the text link, he would see affiliate parameters according to which tracking settings do you use. But the search engine (google) would only see the noscript part in which the link would behave as it hasn't any parameters, e.g. like this: https://www.qualityunit.com