Usually sunroofs are fitted to Sedans and Station Wagons. Their dimension in the Xdirection can vary between 200 and 1，100 mm，and in Y between 600 and 1，100 mm. Theyprovide a number of benefits（cabin sunlight, sky visibility, outdoor feeling, increase ofnatural air flow, winter cabin heating with open sunroofs，quick release of overheated airfrom cabins after a summer stop) offset by a number of relevant problems (waterproofing,rustles and turbulence at speed higher than 80 km/h，breaking risk when made of glass，cabin inner height reduction, dynamic body stiffness reduction)．