With reference to FIG. 2, the walls of the microwave oven 10 may include multiple walls arranged in layers. For example, a metal wall 54 may be provided with an inner wall 50 disposed inside of metal wall 54. Inner wall 50 may be composed of plastic or the like. As shown, inner wall 50 may have several shelf ledges 56 formed therein to provide a surface on which the divider assembly 30 may rest. Inner wall 50 may also have a slot 52 through which a bulbous portion 46 of gasket 44 may extend to make physical and electrical contact with the metal wall 54. Gasket 44 may have a ribbed flange 48 that extends through a slot 42 in the peripheral edge of metal frame 32 with the ribs securing the gasket 44 at the edge of metal frame 32. Metal frame 32 may have a lip 59 that extends under first glass pane 40 to hold it in place. Note that an upper edge of metal frame 32 may contact either tin oxide coating 36 or honeycomb core 38 to provide an electrical path to ground via the gasket 44 and the metal side wall 54.