Straight Arm Linkage, Fits Zenith and Marvel Schebler Tsx Carburetors on Lincoln Sa 200 & 250 gas model welders with Electric Idler . USA MADE! All steel, yellow Zinc plated with Stainless steel set screw. Tig welded collar, slides over .250" shaft. See my other listing for the R-57 Vacuum Idler kit version.