Ok, so the bolt are tiny, and not really bolts at all, they are more like tiny fasteners to hold the wires in place.
No doubt cantilever brakes with this Avid Tri dangle straddle wire hanger looks hot and totally future once mounted, even boring Shimano low-end stuff looks exotic with the Tri dangles. Thrust me, my old Deore DX brakes looked like 200 dollar CNC-protos when polished up and run with these space age cable hangers.
Avid used to be most famous for their Avid Tri align cantilever brake that was one of the first high-end brakes that where easy to adjust (the extreme other end is the Grafton Speed Controller which can be really difficult to set up). Actually, the Avid Tri align brake is still very famous in another way, it is famous for cracking by over tightening the brake pad holder (in the same way the front cap of the Ringle A-headset stem is famous for cracking).
The company was also very famous for their line of high end V-brakes and brake levers. Today Avid is sold to SRAM who also owns Rock Shocks and Grip Shift.
As a seller, I should probably not mention stuff that might make potential purchasers scared of the product for sale, but I can not lie, I am a honest dealer (I think).
These straddle wire hangers are much more difficult to mount than standard one bolt cable hangers. But the price for beauty is often very high, so maybe it is worth it for some of you retro mountain bike enthusiasts. Once they are set up, you will leave them mounted. But setting them up can be a bit more tricky and demands more fiddling than a simple 10mm one bolt system.
One pair of slightly used Avid Tri dangles cable hangers, one in anodized red, the other in anodized black is available for sale to one enthusiast of over engineered cable hangers for only 16 euro! SOLD
One red cable hanger left, yours for 8 euro. SOLD.