Glass Scintillation Vials & Caps are suitable for use with most liquid scintillation counters. Vials are made from Type I borosilicate glass assures the content's integrity with critical dimensional integrity strictly controlled during manufacturing. The reflective properties of the aluminum foil lined caps enhances counting efficiency. This lining system provides an excellent solvent barrier and a tight seal. Choose urea caps for good chemical compatibility or polypropylene caps for good impact strength