The NEBNext Ultra II Directional RNA Second Strand Synthesis Module has been optimized to generate double-stranded cDNA from first-strand cDNA, as part of the NEBNext Directional RNA library preparation workflow. This workflow uses the dUTP method for strand-specific library construction, which depends on incorporation of uracil into the second strand cDNA, enabled by the NEBNext Second Strand Synthesis Reaction Buffer with dUTP Mix, included in this module.