Are reconstructor and mask different?

A hair masque is typically a thick conditioning product that is left on for a certain amount of time. They can be for different things depending on the product. Some of them may have reconstructing properties (containing protein like K-pak) and some are for other things like moisture which is what the Neutrogena Triple Moisture masque is for. The term mask or masque is often interchanged with deep conditioner, conditioning treatment, hair treatment, etc.

Reconstructors are products that contain protein that will bind to the hair and strengthen it. They can be masques, serums, and basic conditioners.

Personally, I like to use the Triple Moisture masque after using K-pak because protein treatments are drying and my hair needs some serious moisture afterward.