If you're looking to amp you're hair condition, Luna is you're Bar! Fortify with Collagen and Biotin to help strengthen hair strands, also know to promote hair growth and prevent hair loss. And Tucuma butter, an excellent choice for damaged hair and add shine to the strands. These mighty bars are concentrated bar of shampoo that can outlast two to three bottles of the liquid stuff. These mighty bars are concentrated bar of shampoo that can outlast two to three bottles of the liquid stuff.