Palmitoyl Pentapeptide-4 is formulated to reach the dermal-epidermal junction, where fibroblasts are thought to read it as a signal to keep producing collagen. “Thought to” is doing real work in that sentence — peptide signalling is an active, evolving area of research, not a closed case, and we would rather say so than round it up to certainty.
Our highest-priced formula, reflecting the ingredient cost of a peptide at a meaningful concentration rather than a luxury markup on packaging.