DEFENDER SiO2 Protectant is the ideal product for professionals and enthusiasts to use as a finishing/maintenance treatment, alongside other coatings or as a stand-alone SiO2 protectant. Defender SiO2 Protectant (DSP) is very easy to apply and use in most environments. Defender creates incredible long-lasting shine, softness and protection. Although Defender is primarily intended for painted surfaces, it can also be used on metal, glass and woodwork.