... outer diameter Maximal 530mm2. Color: black, white, yellow, brown, green, blue, transparent, red, natural etc.3. Hardness (Shore A) :30-904 ... device, molding equpment etc.Rubber Mouldingover 2000 setsWorker 150Staff25QC5Main productso rings, gaskets,custom rubber parts.Material Nitrile(NBR), HNBR, EPDM, ... time15-60 daysMore information Please feel free contact with us Blue color soft silicone o ring