Preventa Standard Counter Pen features built-in Agion Technology to protect the pen as well as chain and a square base to secure the black ink pen in high-traffic areas. Square base adheres firmly to any flat surface. The 24 high-strength ball chain offers enough slack for convenient use. High-density, archival ink is acid-free and water-resistant. Built-in Agion antimicrobial technology offers protection for the pen to suppress bacterial and fungal growth. Pen can be replaced.