Thermo Scientific™ 8mm Autosampler Inserts. 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. Fisherbrand™ 15mm PP Screw Seal, Black, Closed top, 15-425 thread, Assembled septum.