The material is fiberglass-reinforced polyester, as extra strength and stiffness is necessary to make durable products. Side hatches and backdoors have solid double-klick latches. There are covers over the inside lock fittings. Gas springs provide smooth opening and closing mechanisms.The glasses are harden, curved, 5mm thick, slightly darkened and E-marked. Most of the models have glued glass in the back door, which gives great stability and strength. The hardtop is attached to the pickup bed in a way that you avoid drilling into the car. There is a gasket between the bed and the top, so the hardtop will not damage the car.