Once assembled, it holds everything together in a straight line to force things to stay concentric while the adapter is being threaded for the first time. The jig is not needed in the future once the threads have been cut/chased with the adapter.
Adapting ring inserts for each caliber/model of HubTN.4 are included and allow the same jig to work with all of them.
LBRY Tags: hubtn.4; suppressor; 3d2a; fosscad