black polypropylene hole cap, thread for 8-425, PTFE/silicone (red PTFE/creme silicone), septum thickness 1.5 mm, for use with 2 mL vial (standard opening), pkg of 1000 ea. black polypropylene hole cap, thread for 10-425, PTFE/silicone, septum thickness 1.5 mm, for use with 2 mL vial (large opening), pkg of 100 ea.