The fastest-installing GFCI ever now conducts an automatic test every three seconds, ensuring it's always ready to protect. If the device fails the test, the indicator light flashes to signal that the GFCI should be replaced. It also has our proven SafeLock™ Protection feature: if critical components are damaged and protection is lost, power to the receptacle is disconnected.FEATURES and BENEFITS:• Thinner than competitors' GFCI Receptacles: leaves more room for wires in the box.• Auto-Ground clip assures a positive ground to metal box.• Meets 2015 UL requirements.• Feed-thru wiring configuration allows GFCI to protect downstream receptacles.• Prevents line-load reversal miswire: no power to the face or downstream receptacles if wired incorrectly.• Exceeds UL943 voltage surge requirements: survives 100x the required UL 3kA/6kV voltage surge test cycles.• FSUL Listed