Alkali Scientific™ 13 425 Open Top PP Screw Cap with Septa is designed for secure sealing of laboratory vials while allowing convenient syringe access. Manufactured from durable polypropylene (PP), this cap features an open center design with a pre inserted septum, making it ideal for sample storage and repeated needle punctures without compromising seal integrity. The 13 425 thread finish ensures compatibility with standard 13 425 neck vials commonly used in laboratory and analytical applications. The chemically resistant septa provide a reliable barrier to minimize evaporation, contamination, and sample loss. Key Features 13 425 thread finish for standard vial compatibility Open top design for easy syringe access Durable polypropylene (PP) construction Pre assembled septa for secure sealing Chemical resistant and leak resistant Ideal for sampling, storage, and transport 100 caps per pack