Serum Vial Packaging System Components-Complete selection of standard, center tear aluminum seals, Flip Top (Flip off) seals and exclusively manufactured dual tone flip top seals. Dual tone seals provide the advantage of a color coded base aluminum seal, making final product unique even after flip top is removed. Our selection seals and caps work with serum vials, serum bottles and molded vials. Can be used with all crimper systems. Med Lab Supply - Life-Science Products, Chemicals, Medical Supplies, Glassware, Laboratory Supplies & Laboratory Equipment.