rubber wheel stopper 1)Material:natural rubber,silicone, 2)Size and shape:according to your need 3)passed ROHS rubber wheel stopper CertificateISO9001:2000, ... ROHS,SGSTemperature range-40°C-100°CUsagestop air,water,and dustTypeSolid rubber seal,sponge rubber seal,hollow rubber ... stopper,bottle stopper,bottle stopper,bottle stopper, rubber wheel stopper