This Pebeo Crackling Effect Modeling Paste Kit is an acrylic Medium that will create a crackle effect when applied to a surface. It is a two-step process and easy to use. The size and widths of the cracks will vary depending on the thickness that the Crackling Medium is applied. This medium is fully intermixable with acrylic colour and is ideal for use in mixed media approaches to making artworks, as well as for those who are looking to experiment with creating new and exciting surface textures.