BT SCIENCE | Research Supplier Products in Malaysia - Vials . Screw Thread Vials: 4ml: 13-425 Screw Cap(black) with Septa: PTFE/silicone White virgin PTFE PTFE/natural rubber Red PTFE/white silicone Sample Storage Vials: 4ml: 13-425 Screw Cap(white), Closed Top/Open Top : PTFE/natural rubber Red PTFE/white silicone White virgin PTFE: 23x46mm 23x75mm: Headspace Vials (Flat Bottom & Round Bottom