Basically the beans are split. This brand is superb, there's a lot of effort in the design from the box that's unique(can be torn on one side and opened normally on the other) to the umami sauce

Except their natto is average. Kinda watery. What a pity. The umami of the sauce doesn't come through when you mix everything.

Finally I've tried one of every brand from donki. Kajinoya is by far the best and most authentic, the rest of the brands are subpar(up to the individual flavours I've tried)