... plugs has a better seal and solid solid silicon rubber products silicone ladder multilayer plugs has a better seal and ... or harden.We are making rubber products :rubber parts,auto parts,plastic parts silicone masking,rubber molded products etc.we are now applying ... clean ,durable,tastelessflexible,easy to remove and useful material :made of 100% food grade silicone(FDA,SGS)different specifications ...