Cache vintage long black dress crisscross back silk front slit

Cache long black sheath dress with sexy front slit. Crepe textured material. Crisscross back. Tag says Size 10 but this dress runs small. My dress form is a size 4/6 and it fit well. Please use the measurements to confirm fit. I have listed this as a size 4 even though the tag says 10. Flat measurements armpit to armpit 15" waist 14.5" hips 19.5-20" shoulder to hem 55" Slit is 27"