Now here is a 

"Great Idea!"

It's a 4" filter that fits a 1" return!

With up to  365 Day  service life.

Here is how it works!

Simply remove your existing filter and replace it with the ConversionAir. No tools or modifications required. The tapered shape allows the 4" depth to extend into the airway. The rim gasket holds the filter in place and forms a seal to maximize filtration. The ConversionAir quickly and easily "converts" your return air from the use of a 1" filter to this new and innovative 4" design.

The result is a filter that gives you...

• 4 times the media surface area
• 4 times the dust holding capacity
• 4 times the service life

It's the 4" replacement for the 1" filter that lasts for up to 12 full months.

Standard sizes $49.95 plus shipping. Additional sizes priced upon request.