silicone o rings AS568,P.G.et ShoreA50,60,70,80,90 black,white,red,green, ... ,red,green,yellow,blueNSF,FDA,WRAS,TZW,W270,ULAS568,P.G.etc.AdvantageGood Ozone resistance, aging resistance, high/low temperature resistance ... , abrasion resistance, voltage resistance and insulating resistance etc.SizeAS568, P.G Series, ISO 361/1and Customized specificationCertificationISO9001-2008, TS16949, NSF, WRAS ...