... in China ! Best quality o ring 1. material:nbr,viton,silicone,epdm,etc. 2. OEM supplied 3. best quality Hot selling ... in China ! Best quality o ring : Rubber o ring seals ... products,pls feel free to contact me.Best regardslisaSales representativeTianjin Qiantongda Rubber Products Trading Co., Ltd.Add: B-1103,Fanzheng Central Mansion, ...