Pack of 12 Plug Guard electrical outlet coversto protect children and save energy . For child safety, install on any standard 3 prong grounded duplex electrical outlet . E lectrical coverhas two spring loaded sliding plates made from heavy duty plastic outlet cover plates. Recessed outlet openings hold standard 2 or 3 prong plugs. Pull up or push down on cover plate to insert a plug. Each door automatically slides shut when the plug is removed . The foam backing switch gasket fits securely around the electrical outlet for insulation.