I was looking for a respirator to wear while welding and cutting steel that addressed some issues that my other respirator had, and this 3M 7500 series is doing an excellent job of that. I like the fact that your exhaled breath is directed downward to keep from fogging up your face shield and helmet during cold weather, and the mask seems to seal very well around my face. It is, however, not perfect for someone with glasses, but that may be in part due to the size that I ordered. I choose the medium, 7502, and the small 7500 may have been a better fit for me, I'm not sure. Although the respirator with the filters installed looks bulky, it actually fits well under my face shield and welding helmet with no clearance issues at all. The only other area I would like to see changed is with the plastic head cradle. It works very well until you put your helmet or face shield on over it, and then it slowly becomes uncomfortable as the other head gear pushes down upon it.