I attached what a filter assembly should look like if you are going to use the Brackett air filter and keep it in accordance to type design. A. Install the SK-133 (pie pans and bolts) B. Install the Challenger cleanable air filter STC. The filter on the right is so called Brackett assembly, Incomplete. The filter on top is what it should look like with the pie pans installed. the filter on the left is the Challenger filter. The issue is whenever there is a backfire and a small fire, the foam gets burned and crumbles. Without the pans it winds up laying across the carb ventura and shutting down the engine. Been the blame of at least one off airport landing that I know of. A close up view of the "pie pan" installation shows some of the foam clamped on the wrong side of the screen. For best fit in the airbox, I recomend the Challenger filter on Tigers with the pre- 400 S/N (1975-1976) airbox. The Brackett filter fits the later Tigers (1977-1979) much better.