Guys, micro trains sells this type of item for nscale cars and they work quite well. I realize atlas tried this in o guage,but there design was not the best. As you know I have been testing this and it works if done right. Albeit it has some quirks, but it works a lot better than the lobster claws. In ho everything comes with kds now.
Just a couple of points, one a clarification and the other a correction.
N scale manufacturers now use knuckle couplers for all American prototype trains. The switch from Rapido couplers began 20 years ago on new stock. So isn’t just in HO.
HO locomotives and rolling stock do not all use Kadee couplers. They all use knuckle couplers, often of the manufacturer’s own design. The patent on Kadee’s design expired years ago, opening the door for other manufacturers to produce their own and finally replace the hated X2f horn-hook couplers.
In either scale, manufacturers save money doing this by not having to support the profit margin of a third party making couplers.
As for O gauge, you can’t ignore the fact that each manufacturer’s freight cars are different enough to require a third-party firm to have to design and tool up for more truck versions than would be necessary in either N or HO scale. And O gauge is considered the third most popular scale, behind HO and N (at least in terms of number of hobbyists) and O gauge is split by those who prefer scale equipment and those who prefer traditional toy train models. So the economics don’t support the idea of such a venture.
Add to that the number of people on this forum who prefer body-mounted Kadee couplers and you have an even more limited market.
Body-mounted Kadees make sense. Truck-mounted ones are highly unlikely. So you might as well proceed toward body mounting if it is Kadee couplers you want on your equipment.