These high-quality 11 mm glass vials are 2 ml, 12×32 mm and fit most brands of autosamplers. Made of superior quality 33 expansion borosilicate clear Type 1, Class A or 51A Type 1, Class B amber glass, they meet all requirements of US, EU, and JPN Pharmacopia. Easy-to-fill wide-neck opening vials require 6 mm diameter micro-inserts.