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 a 1/8" NPT nozzle jet body with a #70 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.