All struts are made of structural steel, which ensures adequate strength and stiffness. Each strut is powder coated in black mat, under the varnish there is a zinc primer to prevent corrosion. cracking the windshield, recommended in every older car, prevents the sockets from "collapsing" All struts are made of structural steel, which ensures adequate strength and stiffness. Each strut is powder coated in black mat, under the varnish there is a zinc primer to prevent corrosion. : Subaru Impreza STI WRX GD Main advantages and reasons for using struts: stiffening the body better steering the car recommended for sports suspension improves driving comfort prevents cracking the windshield recommended in every older car prevents the sockets from collapsing