The Multi-Kat-Kit contains two additional training discs – an additional amber and green disc – that are to be used in combination with the original amber and green discs that ship with the Litter Kwitter. These discs feature smaller holes than the original discs and are helpful when training more than one cat at a time as they allow smoother transitions between the stages to help slower learners keep up with faster learners. The Multi-Kat-Kit is also useful for particularly stubborn cats who prefer changes to be small and slow.