C20 by Wishtrend, Pure Vitamin C21.5 Advanced Serum, 30 ml, Brightening, Whitening, Skin Tone Improvement, Pure Ascorbic Acid by C2O

It's a great serum if you would like to treat hyper-pigmentation, scars, wrinkles, dark circles, acne and fine lines. I have hormonal acne and use this in my skincare regime. It definitely improved my skin by adding a healthy glow and evening out my skin texture. I've only just started dabbing a little bit around my eyes to lighten my dark circles. My only issue is I forget to use it since you have to store it in the fridge. Also I haven't had an issue with oxidisation (and I've had it for 2 months): I always keep it in the fridge inside the original box.

This is the 3rd bottle I order (in a row) the 3rd faulty! the product is all over the box inside and crusty. I cannot believe it, I ordered before and not a problem and now 3 orders that I have to return… are they just selling faulty items? Not sure what is going on.. I have also reviewed the previous order… such waste of time…

I'm in love with this product it comes on time the only problem is always damaged its my second time ordering it from Amazon but its always damaged. I will love to give it 5 stars please rectify this. That's why I'm giving it 4.

Bottle arrived and it was leaking. Considering this is Vitamin C, I doubt it is still good as it was exposed to oxygen for who knows for how long.

Ce qui m’a le plus bluffé par ce produit c’est l’effet bonne mine et un teint plus lumineux deux trois tâches ce sont estompées les grosses c’est un peu plus complexe mais ça reste un très bon produit que j’utilise matin et soir après avoir nettoyé mon visage bien sûr

Been using this for a year now. Very good and worked. Only bad point is oxidized very quicky

As a big fan of tiam/ost I decided to give this a try thinking that more vitamin c = better, right? Wrong. I use vit c for pore/blackhead control and this product did not deliver, within a month my face was back to being a clogged up mess. It also turned yellow very soon, even when it was kept in it's box and in the fridge, so it's not properly stabilized and I'm not sure it's possible to finish the bottle before it goes off. Though to be fair, it really is far less sticky and it's capable of brightening the skin somewhat, so if that's all you want it might be a decent product for you. I don't think it's worth the £34 (it was £20-ish when I bought it few months ago), I'm back to tiam.

Brightens your skin significantly, acne scars seems to have also gone down, my only issue is that when I wake up in the morning my nails are always orange because the product really grabs on to the nails.

Uso questo siero ormai da diversi mesi e posso dire di trovarmi molto bene. Vista l’alta concentrazione di vitamina C avevo timore potesse creami irritazione e invece nessuno problema! La pelle è molto più compatta e luminosa e i pori meno dilatati. Mi sembra abbia migliorato notevolmente anche le macchie dovute al sole o a vecchi brufoletti. Assolutamente consigliato.

The item has already turned yellow from oxidisation.

The produy was leaking out into the box and had already oxidised, rendering the product useless.

Esta vitamina es muy buena se absorbe muy rápido en la piel la estoy usando hace 3 meses y noto mucho la diferencia veo mintiendo más fina más uniforme

It wasss really really good. It make my skin brighter and even my skin tone. Easy to use and keep, just use two to three drops and put it back in the fridge right after u use to keep it good to use.