Septa 17.5mm for ND18, Silicone blue/PTFE white, 1,3mm, pk/100 Back Catalog number: 17021417 Availability: In the manufacturer's stock Price on request - + Recommended 702632 High temperature septa N 17 HT, red 150,60 € 702628 Silicon septa PTFE, N13 110,78 € 702604 Silicon septa soft, N 11 76,56 €