According to Catrice marketing, this product:
Makes gorgeous lashes even more beautiful in just one month! The highly effective, transparent Lash Growth Serum is proven to lengthen lashes by 25%*. Ideal as a lash-treatment at night, it can also be applied like eyeliner for pampering care during the day. This way, the active ingredients can support growth right from the roots of your lashes. For even longer-looking lashes!
Lash Growth Volume Mascara is a small miracle with a huge effect. The innovative formula of the Lash Plus Lash Growth Volume Mascara is proven to lengthen lashes by 25% *! The special brush supports the application and gives your lashes amazing volume, length and a deep expressive black color at the same time.

I received this as a gift because I really would not go out and buy a "lash growth serum" as I did not believe it would work.
It laid in a draw of mine for a few weeks before I actually decided to give it a fair try.... I had nothing to lose right?

You need to use the two products in conjunction with each other.
The Lash Growth Serum is a clear liner that you apply like you would any liquid liner to the base of your lashes at night.
During the day you apply the mascara to your lashes instead of your usual mascara.

Within a week of using both products I noticed a difference! I could actually tell that my lashes were longer!!!
I was completely blown away and continued to use the treatment for the rest of the month.

After a month I would say my lashes were more then 25% longer, the serum and mascara definitely worked and made a huge difference!

I would recommend this product to anyone who wants to add some length to their lashes... Definitely worth it!