Just Add Water.

Everist's shampoo and conditioner ($24 each) come in a paste format that turns into a foamy lather and serum-like conditioner when activated by water. While the 100 ml tube might appear tiny, it's equivalent to a full-size 300 ml bottle of shampoo. Inspired by the emerging (and environmentally friendly) trend of water-activated tablets in home-care items, Everist co-founders Jessica Stevenson and Jayme Jenkins decided to apply the concept to hair care. [Extracted from the article]