For me, it is conditioners that contain behentrimonium methosulfate:
Behentrimonium Methosulfate
Behentrimonium methosulfate is the mildest hair-detangling ingredient available. It is made from non-genetically modified rapeseed oil. This scientifically sophisticated ingredient is renowned for its superior detangling ability, without causing build-up on the hair. Unlike other hair detanglers, which are known for their irritancy, behentrimonium methosulfate is extremely mild, being recommended for use in baby products which are left on the skin. It is superior in effectiveness and mildness to its commonly used cheaper cousin, behentrimonium chloride. It is not a sulfate.