The Original “Two Stage” Foam Air Filter.

Throughout the years Uni Filter has strived to produce the best, most efficient air filters available. Air filters that not only stop dirt but also increase performance. With this thought in mind, our engineers developed a totally unique concept in air filter filtration – A “Two-Stage” Foam Air Filter. This revolutionary design consisted of literally two air filters in one – an outer filter element made of “course” foam – to stop the large dirt particles – and a inner filter element made of “fine” foam – to stop the “small” dirt like particles.

Our new “Two Stage” air filters not only provided superior air filtration but they also enhanced engine performance and were easier to clean and reuse. Since their conception in the early ’80’s, the Uni Two Stage Air Filter has become the choice of Motorcycle Champions and Serious Off-Road enthusiasts throughout the world! In fact, Uni Foam Air Filters are the “winningest” air filters of all time, winning more Supercross Championships than all the other air filter manufacturers combined!

How a Uni Foam Air Filter works: The air filter is manufactured with “Open Cell” Polyurethane Foam which is wetted with a specially developed foam filter oil. The “sticky” filter oil is suspended in the path of the dirty air on the strands of the web-like cell structure of the foam. This makes it virtually impossible for dirt to pass through the depth of the filter without sticking to the strands.

As the outer strands become loaded with dirt particles, the wetted strands down stream start trapping dirt, allowing the entire thickness of the air filter to be utilized. This prevents surface loading or air restriction for 80% of the service life of the air filter element. When the filter is sufficiently dirty, it can be easily washed, re-oiled and re-used.
Remember, Uni Foam Air Filters MUST be properly oiled before installation!