What does the flustix trustmark on a package mean?

A flustix trustmark means that a particular property of that product has been independently tested and confirmed under a defined certification programme. Which property that is appears in the trustmark itself: plastic-free, plastic-reduced, microplastic-free, recyclable, PFAS-free or with a stated recycled content.

Every trustmark carries a licence number that lets you verify the certificate in the public database. A trustmark is not a general sustainability statement about the company, but evidence for exactly the property named on it.