There exist little red caps that fit onto 66 blocks and binding posts. They're hard to find, though. If someone here knows of the supplier, I'll buy a few hundred.

In the 60's there was a special red ty-wrap that went around/over posts/punches for ""national security"" lines. You had to cut same off to test, and {in theory} requisition a replacement. I've only see same in BSP's so I've no idea if they ever got much use.

I think the BSP called them Special Service Protection, and there was a more stringent version called Special Safeguarding Measures. The latter, IIRC, didn't quite qualify as a military grade Protected Wireline Distribution System, which went to the extents of pressurized conduit with intrusion detectors.

We used to protect leased metallic pairs in a simpler manner; we parked +130 Tip/-130 Ring on same. When Mr. Green put his butt set on same; if his fingers didn't alert him, the BANG in his ear did.

Someone did that once with _stranded_ wire, so the strand was fine enough to puncture the skin. I found myself in a corner with very little recollection of how I got there, and am really not sure that if there had not been a wall there, I would have kept going. Oh well...I didn't freeze to the conductor.