These models construct a 2x4 "Freequenza" rack (Epredia™ 73310017) compatible with fisher scientific Epredia coverplates (Epredia™ 72110013) for use in immunostaining of tissue on slides. This freequenza rack has been optimized to fit within the deck of the OpenTrons T2 liquid handling robot, meaning the base is the size of a standard well plate and should fit in most holders made for these items. A lid is not necessary but if needed the file can be provided.