Clear glass or polypropylene inserts for 8mm HPLC and GC autosampler vials are available in a variety of configurations with usable volumes from 125μL to 200μL. Pricing and Availability. Restek™ Polypropylene Vial Inserts. Specially designed for 2.0mL, 11mm crimp-top and 2.0mL, 9mm short-cap, screw-thread vials. Pricing and Availability.