Caps, Screw Top, with Silicone Rubber / PTFE, ultra-pure Septa, fitted in knurled, polypropylene, Black Caps. For use with 9-425mm thread, 12x32mm autosampler vials, 100/PK

When highest purity in a Septa is required. No color added to the rubber or PTFE (Teflon) for improved purity these caps offer virtually no extractables including colors that can contaminate sensitive analyses.

Often chosen for LCMS, GCMS & LCMS/MS. These Caps can be used as replacement Caps in RSA-Pro X Kits .

Not recommended for Waters® Alliance, Acquity™ and all other autosamplers that require Pre-Slit Septa.