The 3 In. Appliance Spacer Cabinet functions within a package of a minimum of four component panels, the left 4 In. electrical panel SCC4SPEL, the right 4 In. spacer panel item no. SCC4SPER, and your choice of two of the three back panels SCC15SPE, SCC21SPE & SCC25SPE. Place the 3 In. Spacer Cabinet in between two of the back panels giving support to extended appliance runs, acting as a separator between two appliance types, or when you have one appliance of a different height than the others needing to remove the top counter rail as shown in the example package.