This plugin allows you to edit META keywords for one or multiple produts.
You just need to select simple product or product list form category, set or search results and click one button. After that you need to fill new keywords and mark which keywords you want to remove.
This plugins is very easy for SEO optimization and promotion in search engines.
You no need anymore to manualy add same keywords for each product separately. Just choose needed products and add keyword once and it will be added to all products.