Caps, Screw Top, with Silicone Rubber / PTFE Partial Pre-Slit (Y Shape) Septa, fitted in "knurled" polypropylene, Translucent Caps. For use with 9-425 thread, 12x32mm autosampler vials. Excellent for GC and GCMS. MicroSolv Brand. 100/PK.
Partial slit, only in the rubber leaves PTFE to form an evaporation barrier making this a good choice for volatile samples when an autosampler requires a pre-slit Septa.
Y shaped partial slit allows for better "resealing" of rubber after initial injection.