This 5 mm (3/16″) flexible rubber tubing is the right size for connecting 5-6 mm glass tubes in stoppers or other small diameter fittings. It has an inside diameter of 5 mm (3/16″) and a 1.8 mm (1/16″) wall thickness. The outside diameter is 8 mm (5/16″).
It works well for general laboratory use, but is too flexible for vacuum application. This 3/16″ tubing is made of high-grade, medium-wall red rubber and comes in a 3 meter (10 foot) coil. The melting point is 230° F.
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