Very good respirator for welding, grinding, and such EXCEPT FOR:
I purchased this respirator to use while welding, cutting, and grinding on steel, and it would have earned five stars if I had based its rating on filtration performance alone as it was flawless in that respect. The design of the mask and the filters themselves is where I feel the Miller LPR-100 could use improvement. First of all the mask is somewhat bulky out front, and although it fit under my welding helmet, it was touching. Second was the exhale valve directed my breath onto the inside of my helmet and face shield, causing fogging issues when the weather is cold, and lastly I feel that although the replacement filters work great, they become dirty fairly quickly (my first set lasted about two weeks), and they are relatively expensive.
ProsThe mask itself is comfortable to wear and it seals very well against my face.
ConsFogs up your helmet in winter, somewhat bulky (you may have issues with it fitting under your welding helmet, and the replacement filters are kind of expensive.