Ed,
I do not think it is Swiss.
1. The "zig zag" is much different on the Swiss tools and not really a zig-zag pattern, at all.
2. The Swiss piece usually is the piece that screws on to the end of the rod extentions and goes into the barrel first (with a cleaning patch).
This looks like a "coupling" that has other pieces screwing into both end of your brass piece.
Might this brass piece be part of a cleaning kit for a Borchardt ???