contra collection review

It seems that the search results are not relevant to the given question. The search results include reviews and information about the Contra Anniversary Collection, a video game, and a patient guide for Cologuard, a colon cancer screening test. There is no information about a product or collection related to "contra" that includes details about positive, negative, ingredients, or materials. If you have any further information or details about the product or collection you are referring to, please provide them so I can assist you better.