Blue, 12 x 32 mm Snap Neck Cap and PTFE/Silicone Septum, 100/pk - 186000303 | Waters
Corning 8501 TPE Disposable Septum Cap for Storage Tube, White, Non-Sterile, on Mat (Case of 4800): Science Lab Cap Plugs: Amazon.com: Industrial & Scientific
DWK Life Sciences Wheaton Septum Cap - CAP, SEPTUM, SILICONE RUBBER, 3 — Grayline Medical