I had the panacea pulse brake on my old bike and loved it! I have a new 2018 ultra limited. and I have bought a GS-100A strobe controller for led stoplight. on the left it say in, and R+ also says B-. on the right it says out R+ and another B-. I get that the red + goes inline with the blue w/ red stripe brake wire. And I get that unit needs to be grounded. but what is the second B- wire on the out side. any ideas? and am I right on the blue w/red stripe as the brake wire.

 

 

The B wire should just be a passthrough the unit maintaining the ground of the light and possibly grounding the box for it's circuit.