Nioxin System 4 Duo is a two-piece hair care set that includes a 33.8 oz shampoo and a 33.8 oz conditioner. This professional formula is designed to cleanse and condition hair while helping to create a thicker, fuller look. Suitable for normal to fine, chemically treated hair, it supports a healthy scalp environment and leaves hair feeling refreshed.

The set features a color-safe shampoo that removes buildup and excess oils without stripping moisture, paired with a lightweight conditioner that detangles and energizes each strand. Together they help improve hair density and manageability. For best results, use daily as part of your regular hair care routine.

This duo is ideal for those seeking a complete cleansing and conditioning regimen. The convenient large sizes provide long-lasting value, making it a practical choice for daily use. Nioxin is a trusted brand in thickening hair care, and this set delivers a salon-quality experience at home.