PrevaGuard, an EPA registered antimicrobial additive is molded directly into the pen's plastic components. This helps suppress the growth of bacteria, molds, mildew and fungi, especially in high-moisture environments. PrevaGuard includes various elements, such as Zinc, which is known to have many health benefit properties that can help strengthen immunities to various infections. PrevaGuard lasts the life of the plastic, unless the plastic is destroyed.