A dimeric protein complex that contains the co-factors for the ATPase VCP/p97 (Cdc48p in budding yeast). In mammals, this complex consists of UFD1L (UFD1) and NPLOC4 (NPL4). In budding yeast, the complex is a dimer of Ufd1p and Npl4p. [ http://www.ncbi.nlm.nih.gov/pubmed/17289586 http://www.ncbi.nlm.nih.gov/pubmed/10811609 ]