Merck, Z512141-1PAK, Serrated natural rubber septa

General description
Closure has a turnover flange molded to grip outside of container neck, promoting a double seal in conjunction with annular serrations on a hollow plug. Annular serrations depress themselves against the inside wall of the bottle neck, making each serration a suction sealing point.
Note: For extra security when using large bore transfer needles, fasten septum to bottle or flask opening with a wrap-it tie. See ties and accessory tool listings on next page.
Natural rubber septa/sleeve stoppers are used as temporary closures in chemistry, pharmaceuticals, research and development, and biology. These commercially available septa are developed for general applications and are mainly used in labs as closures for glassware, tubes, and cannulation of air-sensitive chemicals.
Features and Benefits

• Precision fit
• Non-contaminating
• Safety and performance