"A" Suffix for JEDEC Standard TVS Diodes: What Does It Mean?

Some JEDEC standard TVS diodes, such as 1.5KE30, will occasionally come available with an ‘A’ suffix, such as 1.5KE30A. What does this ‘A’ suffix mean?

The ‘A’ suffix indicates a bidirectional version of this product, whereas the non-A versions are unidirectional diodes.