This roller is a metal bracket on outside of swingarm made by iron bags circa 1990. It has a nylon roller outside the pin that goes through from front to back. Iron bags is a company who hand makes leather hard bags. In the era of mine, they used a galvanized metal back, with a roughly 6x6 inch extension, maybe 4x4 that covered this roller and when bags are full, makes contact with roller to keep in place , it works great ! Now days iron bags have a form fitted fiberglass back and use no roller.