I thought tri-bumper was at least a semi-technical name for them. I scrounged one from a rummage sale one time and brought it into my local shop before I sharpened my own chains and that’s what he called it. He offered to sharpen it for me and wasn’t going to charge extra despite needing to adjust all three depth gauges but I ended up selling it to a guy with a Homelite who needed that length of chain.Not sure what they are called. There were a couple that go with the bars, and I thought I dropped one of the 20x3/8 semi chisel in there. There are the safety chains used by Home Depot on their rental saws, I have a 5 gallon bucket of them. I cut the "shark fins"(Philbert had a good name for them but I cant remember it) and they will actually self feed very nice in very hard wood with a little extra hook and a 25 degree top plate angle, which really surprised me for how well they hold up. If the top plate was reduced to 20 degrees and less hook they don't feed as well, but they stay sharp a long time and will cut straight(nice in dirty wood too). One of the things I like in a stumping chain is for it to feed well, it's a lot on my back when down there flush cutting, I'd rather sit on the trailer sharpening for a bit so I leave them at 25 degrees and a little extra hook. If you want some let me know.
From what I can tell, the cutter and depth gauge itself is the same as a pro chain, Just has that extra double ramp in front of it.
If a guy had extra time and no pro chains available, he could definitely grind off a.k.a. “spay” those additional ramps as they technically do nothing but prevent kickback. And with good safe use you shouldn’t have any issues anyway. Similar to what I do with low profile 3/8 chains that have that huge bumper tie strap.