Power Up SafelyThe GFCI receptacles conduct an auto-monitor function self-test every 5 seconds, exceeds the UL standards of self-test frequency of 3 hours. Safe & Trustworthy StandardsProtect users, tools, and equipment from dangerous power electric shock with this GFCI adapter. this portable GFCI plug has built-in electronic circuitry that will shut off power if a ground fault is detected. 30-days free return for customers rights and benefits, Lifetime online technical support within 24 hours provided. Satisfaction guarantee. Lighted Power IndicatorSuper tiny LED indicator light has the one-way indication for GFCI properly working condition. Compact SizeThis GFCI adapter is small in size, you can easily put into your toolbox. Wide ApplicationsThe adapter features a NEMA 5-15P three-prong grounded plug and a NEMA 5-15R receptacle. Perfect for dangerous power tools, such as saws, drills, air compressors, lathes, lawn equipment, cutting machines, etc.