O-ring(rubber o-ring,silicone o-ring,nbr o-ring) 1)durable,collapsible,pressurization 2) ... directly according to every client's requirement.1.MerchandiseO-ring(rubber o-ring,silicone o-ring,nbr o-ring)2. MATERIALasbestos fibre ... , rubber and heat-resisting packing material, compressing it to thick paper. ...