A newer and, molecule-wise, somewhat bigger version of the famous "Botox-like" peptide called Acetyl Hexapeptide-8 or Argireline. Just like Argireline, Acetyl Octapeptide-3 is also claimed to influence the muscle contraction process that results in a more relaxed and line-free face, especially around the forehead and the eyes.
While Argireline counts as a pretty well-proven peptide, with multiple studies confirming its anti-wrinkle efficacy, we cannot say the same for Acetyl Octapeptide-3. What we have is the manufacturer's claim that comparing 10% Argireline with 10% SNAP-8 solution (that means 0.005% pure peptide powder) the SNAP-8 peptide did a bit better as it reduced wrinkles by 34.98% vs 27.05% reduction for Argireline (twice a day use for 28 days on 17 women).
Other than that, we can write here pretty much the same as at Argireline. Obviously, no peptide works as effectively as real Botox, and the Botox-inspired peptides are quick fixes rather than being collagen builders or real preventers of structural aging. They are nice additions to an anti-aging skincare routine but not the real superstars (think vitamin C, AHAs or retinol).