I just received this pen today, and I had a hunch about the refills. So I took
apart one of my Jetstream 3 multipens (also purchased from JetPens) and it has
the same size refills as the Hard Lock 3. So now I have a Jetstream Hard Lock
This is a good pen. I used it for a really long time and I bought a whole bunch
more when I went back to Japan. The clip lock does clamp it down pretty good,
but if you pull it firmly enough, you can still slip it off your shirt or
pocket. It writes really well and the ink lasts long. Very firm pen and the
barrel comes in cool colors too.