This pack comes complete with a large size shampoo and conditioner, suitable for hair which is just starting to thin and which has not been coloured or chemically treated. 
 
Nioxin System 1 Litre DUO Pack contains:
Nioxin 3D System 1 Cleanser Shampoo 1L
A gentle, purifying shampoo to support natural hair with light thinning. Large one litre size. 
Nioxin 3D System 1 Scalp Therapy Revitalizing Conditioner
A lightweight, nourishing conditioner set to fortify non-coloured hair which is starting to thin. Large size.