Quoted:
https://www.safariland.com/products/comms-and-hearing-protection/headsets/comms-with-hearing-protection-enhancement/liberator-ii-series/liberator-ii-tactical-headset-with-integrated-digital-hearing-protection-headset-only-or-select-with-tci-tactical-ptt-CTB2_D.html

It is for the push to talk button integrated to a radio.  If you do not have a radio to talk to anyone else with, then those are merely cool factor.  You'll need to figure out what radio system you are working with before you buy the adapter.  Most of us are on Motorola for LEO work.  Some Kenwood.

TCI makes a nice setup with two audio streams, one is ambient, the other is radio.  When stuff gets loud we can still talk to one another via radio without noise cancellation.