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Riffraff Diesel Performance Inc, Engines - Supplies, Equipment & Parts, Eagle Point, OR


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6637 Replacement Cover - Blue

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Made to high standards, these covers are designed to extend the life of your air intake filter while also giving you a way to visually see the amount of dust collected.  The covers work equally well on both oiled and non-oiled filter elements to prevent larger debris from prematurely reducing critical air flow to your engine.

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Product Reviews

Showing reviews 1-10 of 38 | Next

  1. If you use the 6637 filter this is a must 5 Star Review

    Posted by on Sep 19th 2018

    I have loved my Riffraff DIY 6637 since the day I installed it. This is the best prefilter sock I have seen. My air filter lasts so much longer and when I do decide to change the filter it still looks clean. Just wash the sock, hang dryer and bam. The filter ain't cheap so use the sock. I bought a second to trade out when I'm waiting for the other. Thanks Riffraff you have real products that I actually need.

  2. Looks great. 5 Star Review

    Posted by on Feb 28th 2018

    Love the way it looks. I just got it so i will see how it holds up. But love the way it looks.

  3. Great quality and look 5 Star Review

    Posted by on Feb 15th 2018

    The material is top notch and fit perfectly. Looks mean.

  4. Great looking and fitting product 5 Star Review

    Posted by on Feb 12th 2018

    Looks great in the engine bay and the fit was great

  5. Beautiful and well made! 4 Star Review

    Posted by on Apr 25th 2017

    Looks great and fits perfectly.

  6. Prefilter 5 Star Review

    Posted by on Feb 27th 2017

    Great looks...great quality and does what it's supposed to do. Logo looks EXCELLENT.

  7. Looks great ! 5 Star Review

    Posted by on Nov 4th 2016

    If it works half as well as it looks it's all good !!

  8. NIce cover 5 Star Review

    Posted by on Aug 25th 2016

    Worth the money BUY IT.

  9. Nice Cover.. 5 Star Review

    Posted by on Aug 10th 2016

    This also was easy to install around the filter. Still no performance report yet.

  10. perfect sock 5 Star Review

    Posted by on Jul 4th 2016

    This is the best sock you can buy for your Napa gold filter it fits perfect and looks even better
    Looking forward to see how long the filter will last now I have read guys say they have had this set up for 10 plus years can't wait thank you

    Just need it in mossy oak break up email me when and if you do

Showing reviews 1-10 of 38 | Next