It is a standard amount of litter you will be setting on LavvieBot’s litter tray. This way, it enables LavvieBot S to dispense a certain amount of litter automatically to keep its set litter level when the litter gets decreased. If you want to increase the litter level, add cat litter to the tray, and press and hold the LITTER button to change the litter level. When setting the litter level, we recommend filling the litter tray up to the baseline marked inside the tray.