BLUEAIR Classic 500/600 Genuine Particle Replacement Filter; fits 680i, 501, 503, 505, 510, 550E, 555EB, 601, 605, 650E

Works well, efficient.

Yes, they are pricey. Other, cheaper brands of replacement filters may claim to be compatible, but you will be compromising the performance of the unit and may even damage it.I'm not a shill for BlueAir, but we own 7 of their filters and they work great.It's important to understand BlueAIr units do *not* use HEPA filter media, but they *achieve* HEPA filter media performance using a unique combination of an ionization chamber where air is drawn into the unit (imparting a charge to particles in that air) and a filter media which builds up an opposite charge from the friction of air molecules passing through the media. The opposite charge attracts the charged particles in the air stream and binds the particles to the filter media, removing them from the air stream which then passes into the room.This means the unit *as a whole* removes just as many impurities as a HEPA filter, while providing a much higher clean air delivery rate (CADR) over a wider area than a HEPA filter, as HEPA media greatly restricts the airflow due to the high density of the media.Additionally, it is harder for the fan in the unit to push air through denser HEPA filter media, creating back pressure which causes excessive wear on the fan motor.All I can say is our BlueAir units are still going strong after over 20 years of continuous, daily use using authentic BlueAir replacement filters. We've also had some HEPA filter units which took longer to clean the air, only improved the air quality in a portion of a room, were much noisier and eventually became unusable after a few years due to fan motor bearing failure (which made them very noisy, even though they technically still functioned), or the lack of availability of replacement filters.

Great filters

Good quality and better price than the factory.

This review will be most useful for the people that are CONSIDERING a 500 or 600 Series Blueair Air Purifier. I say this because if you have already purchased one, you really don't have choices as far as replacement filters go. These are going to be the best fit and engineered specifically for the air purifiers so it's this or lower level filtration with aftermarket generic filters. I read that Crucial Air makes one but don't fit correctly. Since the money spent in the long run is in replacement filters, the reviews for these filters would ideally be read prior to purchasing the purifiers themselves. I had purchased the Blueair 605 air purifier, which works well. But these OEM replacement filters are bittersweet as far as the value of the purchase goes. and hence a 4 star rating.First and foremost, these are generally $79.99 wherever you go, unless purchase with a 20% off coupon at Bed Bath & Beyond or with a coupon at Kohl's . com (which depending on timing and availability could be up to 30% off). The BB & B coupons are harder to come by...try using an unregistered email address and sign up for emails to get a new coupon. As long as you show the store clerk confirmation of sign up, they will usually give you the 20% off without having received the official coupon. Kohl's best discounts are readily available on their website or on coupon sites used in conjunction with your Kohl's account. Those are the best deals as far as these filters are concerned. The only reason why I bought mine here was because I had a giftcard. These will fit as well as any filters would and would be the benchmark standard as far as filters for these purifiers go. I read reviews about aftermarket filters made for the 500-600 Series and they didn't fit well. Fitment is important because with air purifiers, you don't want air-bypass, meaning you don't want air to go AROUND the filter and be blown out of the purifier unfiltered. So there really isn't much of a choice as far as quality filtration replacements go. The reason for the 4 stars (as opposed to 5) is that the longevity won't generally be 6 months if running 24/7. Blueair advises on changing out the filters 2x per year. Although it depends on how contaminated your environmental air is and whether or not you run the air purifier continually, my experience and speculation is 3 + times per year for clean filtered air. The polypropylene media is fairly thin, meaning that contaminant load capacity is lower than required for just 2 filter changes per year. Yet this material minimizes the filter material from becoming a contaminant which is a good thing. Average quality air purifiers tend to use fibrous media material for filters and they become airborne contaminants as they age. These filters are designed to work with the electrostatic charging mechanism of the air purifier (negatively charges the particles which then stick better to the filters) allowing for capture of 99.97% particulate down to 0.1 microns. Not all air purifiers work this way and they generally catch the industry standard of 99.97% of particulate down to 0.3 microns. I've read reviews and the repeated message is that the filter material had decreased over the years. At close to $80 a pop x 3 changes per year, you are looking at $240/year msrp. Take 20% off if getting a deal at the aforementioned retailers and it will still be $192 + tax / year. There are 3 filters in a pack and most other quality air purifiers have 1 thicker large filter and possibly 1 activated charcoal filter which are recommended to be changed 1 to 2 x per year. It's impossible to do an apples to apples comparison because other brands have filters that have more media but at a higher replacement price and still others will only have 1 filter to replace. From prices seen for other brands' replacement filters and frequency, these prices are average. Other high end brands such as IQAir or Airpura only require 1 filter change recommended at roughly $100 - $150 and could cost less per year. If considering the purifiers that these fit into, these replacement filters will cost you a little bit more annually than other quality brands due to 3 changes/year. But if you find the ability to capture a majority of contaminants down to 0.1 microns in size, you won't go wrong with the air purifiers that these were made for. And if you already have the 500 or 600 Series Air Purifiers, others have said that fitment of generic filters are problematic so this would be the best choice.If you found this review helpful, please let me know!

Yes, these filters are expensive to replace, but are well worth the added cost for the smoke-stop (carbon) filtration to control smells, if that is an issue for you, in addition to the great filtration they provide for allergens. Our 2nd floor NY city apartment unfortunately has unpleasant odors wafting up from the street (or less often, coming from inside the building) -- but these awful smells quickly disappear because of Blueairs running in our bedroom and living room, making city life much more tolerable.Recently, I waited longer than the recommended 6 months to change the filters (due to illness, which distracted me from household issues for a couple of months), so the filters were clogged with dust and other particles by the time I changed then, decreasing the Blueair's function. After I installed new filters, my husband noticed a big improvement in his late spring allergies, and so did I. Highly recommended to improve your allergies and help with unwanted odors!!

I love my Blue air classic 600 filters... the machine is made of metal. It's powerful and it's very quiet... and it's still running perfectly after having it for over 10 years. I take care to wipe it down and vacuum the inside periodically...and change the filters every 6 months or sooner if they are changing color or looking very dusty. I needed to change them out much more frequently when I had cats.I bought off brand filters to save money and they smelled like mildew. Never again. It's so important these filters are handled and packaged properly. Never a problem buying them from Blue Air.