The solid keystone is simple and versatile in design. It can be used to compliment mouldings and casings in various ways, whether the desired effect is subtle or bold. The solid keystone easily enriches windows, doors, entryways, and more. It is crafted in durable urethane and it can be easily attached for instant results. The solid keystone is precision-molded and crafted in high quality polyurethane materials. High-density polyurethane features a closed cell structure that locks out moisture, thereby preventing warping, cracking, staining and decay. This makes the urethane keystone perfect for use in both interior and exterior applications. The solid keystone is pre-primed and ready for installation.