Good balance is imperative between the three of them in order to give reliable protection to the product.
Covert security feature is usually a printed element that can not be seen by the naked eye. A simple aid needs to be utilized. Either magnifying glass or UV fluorescent light or even a smartphone with certain app. This is telling us that we are talking about very small elements or about elements that are not visible to humans’ eye just like that. Apply such an element some special knowledge or access to special equipment or special ink is needed.