Estée Lauder Advanced Night Repair SMR Complex serum, 20ml. Opened one month ago and used about 1/4 of the product, but it didn't suit my skin, so I'm selling it. The red arrow in the third photo indicates the amount when unopened, and the yellow arrow indicates the current remaining amount (please consider this as an estimate). As it's an expensive product, would anyone like to try it before purchasing it themselves? Please refrain from purchasing if you are concerned about it being used. Also, to prevent the cap from coming off, I will secure it with masking tape and wrap it in bubble wrap before shipping. Please understand.