It's a resin made piston filler with a quite big, full ink window, similar to the one Pelikan M200. Overall, it seems rather well made and it's comfortable to write with. One thing which can be annoying is that there's a somewhat sharp step between the orange resin and the ink window, but it's only a problem if you hold the pen high. I tend to hold it very low, so it's not really a huge deal for me. The piston operates smoothly, but I had some problems to get it full. On one draw it filled only like a half of the pen's ink capacity, it required pushing the air out and filling it once more.
The pen posts very well, but for longer writing it's more comfortable to write without posting as it gets a bit back heavy.
I ordered it with a "flex nib". Out of the box it was very scratchy. I polished it with a three grit nail file (which serves me as a budget alternative to micromesh pads) and now it's much better.
The "flex" thing is another issue. I didn't really know what to expect, I've never before had a modern, steel flex nib. Line variation is definitely possible, but requires a strong pressure and seems to come from the fact that the nib tines were made overly long, rather than any properties of the material. The slit ends only right under the section. Then again, I didn't have much expectations, so I'm fine with that. After I made it more smooth, it became a very pleasant, wet and springy medium nib.
Compared in size with Kaigelu 316 and Pelikan 400NN
Edited by WJM, 14 February 2018 - 11:02.