Final heterodimeric neurohormone released at the end of the molting cycle, involved in the sclerotization (tanning) of the insect cuticle, melanization and wing spreading. Heterodimer specifically activates the G protein-coupled receptor rk. Heterodimer with Burs; 2 cystine knot polypeptides. Coexpressed with CCAP in most CCAP-specific neurons. Coexpressed with Burs in 4 bilateral neurons in thoracic and abdominal neuromeres of the ventral nervous system. Expression is low in larval stages and increases before ecdysis; consistent with role in postecdysial cuticle changes.