Lightest Hydration, Unique Product
I’m a big fan of The Ordinary brand, and this is my favorite product in the line.  This is the LIGHTEST product for hydration.  It has a viscosity/thickness just a little heavier than water.  It is much thinner than most serums.  It goes on like water and absorbs quickly with no residue.  It is a great first step after cleansing your face.  It is truly weightless, so you can layer serums over it.  You will likely still want to use a cream/lotion moisturizer, but you’ll need less of it.  You can use this product under Vitamin C, Retinol, or leave-on Lactic Acid serums.  I have very sensitive skin, and it did not cause any irritation.  I like this product because it is unique; I haven’t found anything like it, especially for the price.  This product is Vegan.  It does not contain SPF.
Rating: 5 stars