One panel goes between the ring and spacer, while the other is flush against the rear blower cover. A test port in the spacer accepts an Enderle nozzle jet and hose which allows you to check the inner burst panel in case it has failed.
The inner frame is made from billet alum. and O-ringed for a superior seal. The kit comes with an inner burst panel frame and O-rings. Frame measures 6.125" x 3.125" and will work well with most industry standard twenty four bolt outer frames or burst panel diverters.