Pretty soon after the Render K was produced, Karas Kustoms made a few special runs of different materials and finishes to test the waters. The Delrin version has been given quite a bit exposure here on The Clicky Post, but there is one called the raw-bar stock version that hasn't been seen too much.
Bill Karas was kind enough to provide me this pen to have and review, and I think this thing is absolutely cool!
What makes this pen interesting is that it is made from the same bar-stock of aluminum as the regular Render K, but the barrel of the pen received no machining or taper. The inner parts of the pen, grip, and threading are machined, but the barrel is left the same diameter (just about 1/2") as when it came to Karas as the raw "rods" of aluminum that they load into the machine. The outside is rough, and even still contains the marks from when it was moved through the chuck of the lathe.
Since the pen hasn't been tapered that means it retained more material and weight which makes it a bit heftier than the polished version. If feels super solid in your hand.
Like the other Render Ks, this one also takes the Hi Tec C or the Parker style refills (and Schmidt Easy Flow). With a spacer, it will also take the Fisher Space Pen refill which I think is personally a dynamite combo with this sturdy beast.
Now, for the good news. There are still some of these left if anyone was interested. They aren't listed on Karas' site, but they made a post awhile ago on their blog about these as well as the Delrins.
These may not be right for everyone, but they sure would make a really cool raw, industrial gift for someone that would appreciate the unfinished look and feel these carry. (or for yourself to enjoy...)