... size 3.Used for glass bottle,pot,canister,tube, Pipe rubber stopper for test tube 1. Material: 100% Food grade silicone 2. Size: Different ... available. StandardOrNonstandard:Style: Size and Color:Material: Nonstandardrubber stopper for test tubeas your requests,drawings or samplesRubber(NBR,SI, Viton,EPDM ... zone, Haining City, Zhejiang province, China Zip314419 rubber stopper for test tube