line lock not releasing?

TrailBeast said
With the lock disconnected or off, you should be able to blow through it both directions with near zero resistance.

I tried blowing through it when I first installed it, there was definitely some resistance (hard to tell how much, but more then "near zero" for sure)

65wgn440 said
I was told by a local (Ohio) parts rep that those fittings are not DOT approved for small diameter brake line use. Wall thickness, using for repairs on old line, loosening/re-tightening failures, were a couple issues I think he mentioned. Not always just about burst pressures. That was maybe 1-2yrs ago, though, maybe things have changed.

Gotcha, I can see how someone could use these to splice a broken line, and how that would be an issue