I recently got his affordable, tiny Vitamin C serum by Manyo Factory - including 2 samples. Manyo Factory is a Korean brand that focuses on combining "natural" ingredients with popular active ingredients. This VC serum has 10 percent L-Ascorbic Acid (LAA) and a bunch of other ingredients (fruit and plant extracts),
To "activate" the serum you simply press down the cap like a button and then shake well. Afterwards you take off the cap and replace it with the dropper.
Ingredients: sea buckthorn, ascorbic acid, butyleneglycol, glycerin, Niacinamide, lemon extract myrciaria, myrciaria seed extract, rosehip extract, citron extract, polyglyceryl-10 myristate, polyglyceryl-10 laurat, Masha extract, licorice extract, Lactobacillus, fermented yeast filtrate extract, cherry fruit, propanediol, beta-glucan, bilberry extract, grape seed extract, orange extract, black cherry extract, tomato extract, apricot extract, zanthoxylum extract, Pulsatilla vulgaris, usnea barbata extract, lavender angustifolia extract, acerola cherry extract, ziziphus extract, litsea cubeba. (from http://manyo-factory.com/en/shop/product/white-vita-c-liquid-serum-osvetliaiushchaia-syvorotka-s-vitaminom-s-dlia-litsa)
So how effective is this? First of all, it smells like an energy drink with orange and lemon. Usually VC serums don't smell good if there is no added fragrance or have almost no smell. I am a bit woriied about this strong scent because it means there is a lot of CITRUS inside - and I don't like citrus in skincare (though I currently also use Hadalabo Whitening Cleanser which smells like lemon).
Anyway, the serum is more liquid than the NuFountain and Timeless VC serums and less sticky. I give it 10-15 minutes to absorb and brighten my skin and then follow with moisturizing products and sunscreen.
It is less effective then the Timeless VC serum which has 20% LAA and ferulic acid. So if I finish it I will go back to the Timeless serum which has 30ml (but of course it oxidizes after 2 months so half of the bottle is left).
I paid only 62rmb for this but the bottle is also tiny, only 10ml. It is supposed to be used up within a month. I am surprised that on their international website they sell the serum for 23$. That is quite expensive. If I didn't live in China where I can get Korean stuff VERY CHEAP, I wouldn't even bother... Just use Timeless (cheaper) or NuFountain (22$), though the NuFountain serums oxidize within a month.