This is a weird refill shape and size. Heck, I don’t even know what you would call it. It’s small and skinny, close to multi pen size, and has tiny wings on the side of the barrel. I didn’t think there was any way I could find a better refill to put into it.
And I was wrong!
Turns out, there are other Japanese pens that take this style of refill, and both Pilot and Uni make ones that match. There is even a Hi-Tec-C model, which I have subsequently ordered two of (black and blue 0.4 mm) for my Ohto Horizon. Maybe it can be my perfect pen after all.
I must not be the only one who thinks that, because at the time of writing they are sold out at JetPens. And they should be. The barrel colors look fantastic, the pen feels great, and it’s only $8.50. I think you are going to be seeing a lot of this pen, especially in my pocket.