Hey AGG (Anthony) or other HKRKI's - have you ever seen a G3 trigger housing like this with electrical components inside. I've never seen anything like it.
It came with a G3 parts kit ordered from Centerfire Systems.
I had to zoom in on the 'guts' and can see an electrical contact/toggle device that appears to be in line with the selector. Appears to be ripped out of whatever it was attached to as the electrical wiring insulation is missing. Some sort of training or evil prank device that's attached to trigger and shocks the piss out of someone when they flip the selector to fire and touch the trigger (is my guess).
It's unusual to find electrical components inside a G3 trigger housing from a standard parts kit. This suggests it might be a custom modification aimed at enhancing the rifle's functionality, possibly with electronic triggers or similar upgrades.