The Beast 20 delivers maximum stability with exceptional cushioning. Using the Brooks’ GuideRails technology, the Beast provides superior motion control with less weight. The GuideRails act like bowling alley bumpers to keep your feet and knees properly aligned through your entire stride and mitigating excess side-to-side movement. Underneath is the BioMoGo DNA midsole for responsive cushioning and shock absorption. The drop is approximately 12 mm.