3M501 Filter Retainer Lot of 2

Snaps right in place and holds the pre-filter just as described.

Safety Equipment is one of those things we want to protect ourselves. The quality of this product is great for my needs. The price is right with the standard of others.

Wether you use it on a dust filter or as a pre filter on a cartridge,, it does a great job.

There are many imitators, but the 3M brand is the one that fits the best. It is actually probably a little “over snug” in fit — it can be a little difficult to put on, and a even more difficult to remove.I have four non-3M brand covers that came as part of a mask and filter cartridge packages which I use for non-critical filter situations. Only one of those covers stays on, the other 3 sets fall off if bumped — not good if your pre-filter drops in dirt, dust, sawdust, paint, etc.When it matters, stick with the 3M brand covers and filters. No, I don’t work for 3M, but I do trust their products the most. :)

El producto muy bueno. La rapidez de la entrega, recomendado.

Had others that keep falling and cracking, this gray or grey unobtainium material they use is pretty good.

I love these, and I’m so glad I found them. I do a lot of spray painting, and ruining expensive cartridges was getting expensive. I found that I can pair these with a set of 3M part number 603's and 3M 5P71 or 5N11 cotton filters, and they still block 99% of the paint.I say 99% because I don't believe any paint mist comes through. But I didn't do any scientific tests… I’m primarily using the “painted nostril hair” test. If you had any doubts, you could probably stuff two cotton filters in there.If you’ve got an oil based paint or something more dangerous, they also fit over regular 3M 6000 series cartridges. So this would be a pre-filter over your expensive filters to keep paint and dust from clogging them up and make them last longer. A great little accessory.Hope some of this helps!

These held the filter packs perfectly.