This flange system was designed to further advance duct joining systems that were available to the industry.

By maintaining the principle flange profile and taking it further by rolling directly onto the coil along duct ends. With this method potential leakeage was greatly diminished to within the TM1 allowable leakage rates.

Secondly, on deflection, J6 with tie rods was achieved with 30mm profile as opposed to the necessary 40mm with slide on flange.

Quicker, neater and stronger.