The most obvious effect I noticed was the volume I had the next day, after washing.
I massage it in the evening, twice a week, and the next day I wash.
I tried not to wash, but I didn't like the feeling that remained.
But I put quite a lot, I think that applied less, especially on short or medium hair, it will be much easier to tolerate/style the next day.
The Ordinary
Multi-Peptide Serum for Hair Density 60 ml