English to Dutch Other Art, Arts & Crafts, Painting

It is a part that is included in a package to create a framed print of a baby's hand or foot.

Translating word for word I get: "zuurvrije afgeschuinde matten", but I can't find any references online about what these might be exactly, and how it translated to Dutch.

I am looking for the best Dutch equivalent, target audience is general consumers (new parents).

Thank you!