Whitepost System DC 1 Color Coded Refill Posts, 5/Box. Tapered posts are made of fiberglass composite and high-strength epoxy resin. High fracture resistance with a modulus of elasticity similar to dentin. Radiopaque yet excellent light transmission, assisting in photopolymerization of cement. Provides intraradicular reinforcement of dental structures and promotes retention for restorative or core build-up material, indirect restoration