Adjustable All-Purpose Acrylic Channel or Cavity Tissue/Brain Matrice. Acrylic all-purpose tissue/brain matrice has an adjustable cutting width and can be used to generate 1mm incremental thick sections in all types of tissues. The adjustable length of cutting surface is from 1mm to 25mm. The flexibility of these acrylic matrices makes it ideal for many different tissue-slicing functions. Order S for a sagittal style, and C for a coronal style.