Leviton 8490-IGB 20 Amp, 125 Volt, 4-In-1 Receptacle, Straight Blade, Industrial Series Extra Heavy Duty Hospital Grade, Isolated Ground, Surge with Indicator Light, Blue Terminal Wiring Screws fit Inside a Standard Single Gang Wall box; Adapter Plate not Required (Optional) Impact Resistant Nylon Cover and Base for Strength and Resistance to Chemicals and Corrosives Easy-to-Read Voltage and Amperage Rating Molded onto Smooth Face Extra Heavy-Duty, T-Type Triple-Wipe Bronze Contacts for Maximum Performance Convenient Built-in Strip Gauge