Petal Fresh Thickening Biotin & Castor Oil With Caffeine Conditioner 475mlachieve thicker, fuller, and more vibrant hair with Petal FreshPure Thickening Conditioner. Let the Caffeine stimulate your hair, promoting healthy growth and adding noticeable thickness, while the nourishing Biotin & Castor Oil works its magic to strengthen and revive your strands from root to tip.