Not sure but it looks similar to a lot of early PA designs. There are a ton of nock offs out there and others. In my experience they all work fairly well. Some have small accuracy issue because of the way they vent the gas but all of them reduce recoil to varying degrees. Like I stated to the OP earlier several smiths have there own breaks that they install. It could be just a custom by a particular smith. That style of break in my opinion works the best. I prefer a little more directional venting than that appears to have, but I have several that are almost identical to it and they just work.
