The Safeguard Medical SIMBODIES IO Replacement Bones Proximal Tibia Set is a professional clinical simulation component designed for intraosseous (IO) access training. Crafted from advanced composite materials, these replacement inserts accurately mimic the outer cortical bone and inner medullary cavity resistance of a human tibia. They fit securely into compatible proximal tibia training legs, providing emergency medical responders, trauma nurses, and military medics with the exact tactile feedback required to master needle insertion techniques.