These were both found in 2017 on the same abandoned line but a few miles from each other. The one on the left is the more narrower dome and it has some nice amber streaks in it.
The one on the right is the more cannonball shaped dome but it has a piece of glass that popped off the dome most likely due to frost since it was found upside down and half buried in the ground. I haven't yet glued it back together but I'll get around to it
From what I'm told these insulators are the threaded version of the 743.1
CD 143.1