20/40 used in North Dakota 1.Passed ISO & API 2.Tested ... .Our products have the following advantages:1.High conductivity2.High crush rate3.low costOur products can be classified as follows:1 ... mesh, 16-30 mesh, 20-40 mesh, 30-50 mesh, 30-60 mesh, 40-60 mesh, 40-70 mesh, 70-140 mesh, etc ... Fax:+86.387.86631068 www.toproppant.com NO.4 20/40 used in North Dakota