That's the .22TCM9r, the only difference between the two is the bullet. The .22TCM uses a 40gr factory projectile, and the -9r uses the 39gr factory projectile. Armscor created the -9r so the round would fit into a standard Glock17 9mm magaine. It's a funny looking round when you hold it in your hand. That's the conversion kit I'm running in a Glock 17. I have a set of reloading dies that will work with either round (again, it's just the OAL difference between the two factory bullets), I just haven't used them because I bought a case of -9r ammunition so I would have reloadable cases after I shot them all. Then I was going to slowly work up a load to the fastest velocity I safely could. That was the plan, but the reliability is only 90% or so. I went and bought an aftermarket slide (Rockslide USA) with a bunch of lightening cuts, hoping to increase the reliability. The conversion recoil spring is weaker than the stock unit, and sometimes fails to get the stock GLock17 slide into battery. Maybe the lighter slide will help, maybe not.