Available in two sizes: 33.8 oz / 1 L or 128 oz / 1 Gallon Dry hair starts losing the battle at the shampoo step. Biolage HydraSource Shampoo is a nourishing shampoo formulated to gently cleanse dry hair while restoring softness, moisture, and manageability — one of the best shampoos for dry hair for both daily home use and professional salon settings. Professional Benefits Gently cleanses dry hair without stripping moisture or natural oils Restores softness and manageability from the very first wash Nourishing formula prepares hair to absorb treatments more effectively Safe for daily use on dry, dehydrated, and color-treated hair Gallon size ideal for salon use and clients with long or thick hair How to Use Apply to wet hair and massage gently from scalp to ends Work into a light, even lather Leave on for 1 to 2 minutes for additional hydrating benefit Rinse thoroughly with lukewarm water Follow with HydraSource Conditioning Balm or Deep Treatment Pack Pro Tip: For best results, leave this nourishing shampoo on for 2 minutes before rinsing. The extra contact time allows the hydrating agents to work at the cleansing step. Not just the conditioning step.