Sigma flat bottom headspace gas chromatography metal cap hplc vial caps in amber for Aijiren autosampler for sale Sigma. Aijiren 18mm crimp top headspace vials with flat bottom for The Chromatography Direct range of 20mm Crimp Top Headspace Vials and Caps are available in 20ml Amber and Clear, 10ml and 6ml in a variety of flat and round bottom – suitable for CTC, Perkin Elmer