If your catch basin is at an odd height, there’s an easy way to fix that. Just dig out a little deeper and add a riser. FDM's Catch Basin riser adds 2 inches of height. If you need more than 2 inches of lift, simply stack the risers on top of each other and build to your desired height. Fits any of FDM's 4" Pop-Ups and FDM's 4" Catch Basin.