Aeroflow's soft mount vacuum line fitting is designed to be inserted into a silicone hose. Simply punch an 8mm (5/16) hole into the silicone connector and install. Each kit includes a CNC machined aluminum fitting, lock nut, washer and O-ring seal. This fitting is designed to seal perfectly for all different silicone hose wall thicknesses. For use with Aeroflow 6mm (1/4) I.D. vacuum hoses.