Renown’s ‘DTC’ Drop-Thru Crisscross Flow Sub is used alongside Renown’s patented one-trip isolation system to allow for gravel packing, liner isolation, and pressure testing all in one-trip of pipe. The tool allows forward circulation out the bottom of the inner-string to help achieve setting depths in gravel pack operations. Once on depth a shifting ball is dropped directing circulation flow out the side of the tool, allowing sand or gravel overtop of the liner packer. Once a satisfactory volume of slurry is pumped, a secondary shifting ball is dropped to close the annular directed flow and will release the initial shifting ball to be seated below.