Seals and septa for headspace crimp seal vials, 20 mm. Catalog Number: (WHEA20-0050AT) Limited time offers. Supplier: DWK Life Sciences. Description: MicroLiter, N/A, Chromatography vial closure, Ø (mm): 20 mm, AlumiTin™ seals with septa, green, large opening, Septum: Natural PTFE/blue silicone. UOM: 1 * 100 items.