Protection Against Stone Chips
A question i am ask quite regularly is will a paint sealant, paint protection or a wax protect my paint work against stone chips, unfortunetly no wax or sealant that we know of offer any protection whatsoever against stone chips; the final thickness of the protective coating of a wax or sealant (even when heavily layered) is always much less than 1 micron thick which equals 0.001mm in thickness, a high speed impact with stones and other road debris will penetrate this easily, and at a thickness of 0.001mm its quite obvious that this protective coating is not going to protect against stone chips.
Your only option for added protection against such damage is to have a clear film covering. These clear vinyl films are several hundred microns = 1mm thick and protect against stone chip damage fairly well, but their qualities are typically poor in terms of reflectivity and clarity, and they are expensive to fit.
Typically it is best to allow stone chips to accumulate over time and have the affected panels resprayed every 18 - 24 months. This is no more costly than having a clear film fitted.