Monofilament

Monofilament are essentially small strands that were so small that they were capable of slicing atoms. No form of defense was known to repel monofilament strands.

The Federation were aware of the technology, however, they are incapable of utilizing it as the strands would become unstable and collapse.

The Hive species had developed the technology to replicate and maintain monofilaments. They were able to use such technology as a form of weapons in their fighter craft with them maintaining a monofilament strand betwen them and head towards enemy starships which would be ripped apart regardless if shields were functional or not. They developed this even further with the development of monofilament torpedoes which would explode and shower a region with the strands which was capable of destroying a large number of enemy starships that were clustered together.

(DS9 episode: Objective: Bajor)