A protein conditioner might also be called a reconstructor. Also, look at the ingredients; protein conditioners will often have a protein mentioned within the ingredients (ie: wheat protein or animal protein). When you read the description of what the conditioner does, a protein conditioner will refer to things like strengthening, rebuilding and/or reconstructing hair. An concentrated protein conditioner will also advise that you rinse the hair for at least one or two minutes after use. For example, Nexxus Keraphix, Aubreys GPB, Aphogee and Nexxus Emergencee are protein conditioners (the latter three are concentrated). The label on moisturizing conditioners will often state that it infuses moisture, or hydrates the hair, or imparts softness. Nexxus Humectress, Motions Moisture Plus, and Mizani Moisturefuse are examples of moisturizing conditioners. I hope this helps.