A protein-containing complex composed of a stem-loop binding protein (in most species SLBP) and its interacting partner (SLIP1 or MIF4GD in most species) that binds to the histone mRNA (hmRNA) 3-prime-stem-loop structure. Facilitates hmRNA translation initiation and may also be involved in its processing and nuclear export. [ http://www.ncbi.nlm.nih.gov/pubmed/18025107 http://www.ncbi.nlm.nih.gov/pubmed/23286197 ]