Our decorative pieces may be cut, sanded, nailed, and basically installed the same way as any wooden product.Advantages of Polyurethane:1. Interior and exterior use.2. Waterproof: they won't absorb moisture or mildew3. Lightweight and easy to install.4. Pre-primed and ready for paint (Note: Primer does not absorb stains)Great decor for over windows and doorways.