When looking at anything with compressed gasses, keep in mind that the actual CFM (cubic feet per minute) is highly variable based on supply pressure, temperature, specific gravity, etc. There is a way of standardizing things to a standard cubic feet per minute (SCFM) at standardized conditions, but I don't thing the Chicago tools and harbor freights do this. Long story short, with compressor ratings and tool consumption ratings, it is very easy to play games with their CFM numbers, so keep this in mind if you are ever purchasing anything and trying to match up supply and demand numbers. Need a little margin in there.
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