Dynarex LabChoice Flange Plug Caps are designed to help provide a secure seal for test tubes, centrifuge tubes, round cuvettes, and more. These Caps are manufactured from sturdy plastic materials for optimal durability. Two flexible flanges provide a firm fit for improved leak resistance. Dynarex LabChoice Flange Plug Caps are available in a variety of sizes to suit a wide range of needs. 1000 PER BAG, 10 BAGS PER CASE