Precise 2 Face Black Granite Parallels 1" x 2" x 12" 

• Precision ground in pairs
• Can be matched in matched pairs with two faces or four face parallel
• Grade A. Flatness and beeline of measuring surface 0.00005”/6”, parallelism of the two measuring surfaces 0.00005”/6”, perpendicularity between measuring surface and side surfaces 0.0008” /4”, height difference of the parallels within a matched pair 0.00005”/6”