"Very sensitive tester, putting it near a socket immediately buzzes and lights up. For peace of mind you can't go wrong, comes with battery too! It is able to detect some static electric on human skin or clothing too if you rub it in!"
"This come with batteries AAA; set up is 10seconds and you are ready to go. Test it on live circuit to make sure it detects correctly - just a prereq. Good quality. Provides visual and sound alerts. Glad I have bought it. Good reviews. Can't say much about reliability, as just bought it."