What are aluminum extrusion general tolerances and your standard? What are aluminum extrusion general tolerances and your standard? The aluminum extrusions we supply meet the tolerances outlined by GB/T 5237.1-2017 (Aluminium alloy extruded profiles for architecture—Part 1:Mill finish profiles). The main standard for aluminum extrusion tolerances is GB/T 5237.1-2017, However, where tighter tolerances are needed, […]