They give outside dimensions of the unit , but didn't see inside .
This works best for old congealed grease.I always boil parts in washing soda.
All the grease crud and oils will float on the top.
A second dunk in plain boiling water will remove any accumulated oils after pulling the parts out of the first bath.
Just be mindful of leaving parts settle to the bottom of the pot and resting directly on the heat source for too long a period.