I recommend Mise en Scène Black Truffle Oil Hair Serum.

Mise en Scène makes great hair products, so I have been using their other items for a while. I happened to buy this product recently and have been using it, and I recommend it because it is good. In particular, it has a large quantity and a reasonable price, so it is great for those looking for an affordable serum. It is even better because not much gets on my hands after applying it to my hair!