Sample Vial Snap Cap found in: Sample Vials, PP, with LDPE Snap-On Caps, 20mm snap cap for 10 and 5mL sampl vials, 11mm Snap Top Caps , Snap Cap Vial.. ease of sample tracking and superior cap seal. The free-standing CryoELITE vial has a purpose-designed bottom which can accommodate the Wheaton 2D Matrix Bar Coded Insert for traceability. . The insert is easily pressed to fit into the vial