This product promises an immediate whitening effect thanks to the use of serum. - Brand: Yunth - Product Name: Pure VC Whitening Serum - Contents: 1ml x 28 - Made in: Japan - How to use: Fresh serum with a 30-second expiration Thank you for viewing. I have an extra one from my regular subscription, so I am offering this item for sale. This is a new, unopened product.