China Chromatography Vials manufacturer, Glass Vials, Glass 2021/7/30 · Bonded Cap: Septa Glued on Cap, So septa not Fall from Cap. Crimp Seal Vials at Thomas Scientific. to crimp than tin 20mm seals. The sealing surface is aluminum and the inner diameter is made of tin to add the magnetic surface. These caps are available 20 mm Magnetic Cap