Same design as the 219FTH from what I can see, flat links instead of figure 8. Normally stronger as a result. A lot of 350/400/500/550 owners are now fitting them in preference to the normal 219H chains, I've sold loads of them, hardest part is cutting and rejoining the chain to the same standard as the factory, I had to buy a factory tool to do that at great expense, they are quieter in operation as well and reduce wear on the camchain tensioner. Tsubaki are still around.