Multi-bore tubing is two or more tubes that are extruded as a single piece. The tubes are joined with a tough connecting web. This tubing is ideal for applications that encounter severe or constant flexing which might separate the bond on MCR tubing assemblies. A small rib runs the length of one of the tubes for easy identification. All Multi-Bore tubing is mono-colored and is recommended for use with barbed fittings. Pushto-connect fittings are not recommended, the slightly flat surface resulting from stripping may affect the fittings sealing abilities.