All photo,picture and mirror frames are made of natural resin, , through 13 processes. The lifetime of frames made of Natural resin and glass fire are more than 50 years, the same as buildings. COST COMPARATION: The cost of resin and glass fire products is 1.5 times of PV foam materials,3 times of oxidase materials,5 times of gypsum materials. LIFETIME COMPARATION: Resin and glass fire frames lifetime is more than 50 years, while PV foam materials is between 15 and 20 years, oxidase materials between 5 and 8 years, gypsum materials around 3 years.