This is used with the unistrut (070007843 and -844), which are attached to the tops of the wooden kickbacks. These plates are located on top of the unistrut where the front end frame feet (two per side) will be located. This plate is held in place with a unistrut nut inside the unistrut and a jam nut on top of the plate, both screwed onto the jackscrew that passes thru hole in the plate and is tightened to the bottom of the unistrutCompatible with: XLi EDGE, 90 XLi, 8290 - 90 XL, 8800, 8270