Detailed Product Description Standard size(Inch) Outside Diameter(mm) Wall (mm) 3/16 4.75 0.76 1/4 6.35 0.76 5/16 7.94 0.81 3/8 9.52 0.81 1/2 12.7 0.81 5/8 15.88 0.889 3/4 19.05 0.889 3/4 19.05 1.07 7/8 22.23 1.14