i pulled the metal bushing caps off the old arms and cant find them. so measuring them would be inaccurate. I was skeptic of the lower priced POL arms and asked them where made? I was told a small shop in California manufactured them for POL ?? They look exactly like the arms that PST sells which i was told a small co. in the mid west manufactures for PST ? Hell IDK. guess we will see if the QA1 arms fit up in there. For what its worth, there is no greasing these up and knocking them in. If it was remotely close i would give it a shot.