To ensure fitment compatibility, some products need more details
beyond the base fitment Year-Make-Model (YMM). If a user is searching
for a tonneau cover, they would need to specify the YMM and the
bed length as well to ensure the right fit. If they were searching for
an engine part, they would need to specify the YMM and the engine
displacement as well to ensure that the product they’re buying is
compatible with their car’s engine. In both examples, it’s the combination
of the YMM and part type that determine what additional fitment detail
is relevant. This additional fitment detail is the application qualifier.