The term SiSA stands for Silver-ion Surface Assurance. Silver is a natural element with antimicrobial properties which protects the surface against 99% of microbes.
Cross-contamination is one of the most common ways to spread germs, thus at PURE Drinkware we pride ourselves on incorporating our SiSA antimicrobial technology into every surface from top to bottom of all our products (exterior surface, lid and even the non-slip silicon base)