Short Thread Vials and Micro-Vials ND9 with assembled Short Thread Seals ND9 Pre-screwed vials reduce the risk of contamination of vials in laboratories. Furthermore special applications could require a pre-screwed vial (e.g. in the tobacco industry). Pre-screwed vials are available with any of the short thread vials and any seal of your choice. This product is an alternative to the products (SKU) of these brands: Agilent:- Waters:- Chromacol:- National Scientific: C4000-196W / 100 - Wheaton:- Finneran:- SUN/SRI International:Meer tonenMinder tonen