Good crush size for high efficiency and bed fluidity

The below image is a high definition picture to provide detail of a good crush size that removes the grain husk while leaving it intact, and cracks the grain open without pulverizing it. The husks are useful for keeping the grain bed from compressing, and a lot of grain powder will become gummy, plugging the gaps in the grain bed and preventing water/wort from properly draining through. This crush was obtained with a single pass through a 0.04"/1mm roller gap on a three roller Monster Mill.

Good crush size for mash efficiency and bed fluidity