This fitting allows your to branch off two additional dust hoses off your main line. All four ends have a 100mm outside diameter to fit to industry standard 102mm internal diameter dust hose.This hose fitting is made from a thermoplastic polymer, which is impact resistant, has structural strength and stiffness and will not flex or distort under pressure. It has excellent low temperature properties and will perform in extremely cold workshops down to -40°C. The internal bore is smooth to ensure the smooth passage of dust. As all of our fittings are made to exacting and tight tolerances to prevent air loss, a top tip is to use a washing up liquid as a lubricant when initially installing a 100mm outside diameter to fit to industry standard 102mm internal diameter dust hose. ©