HART Professional 9 LED Stud Finder with Live Wire Meter. With a HART stud finder, you have the fastest, easiest, most accurate stud finder on the market. There is no calibration procedure. You can instantly find studs. Once you have it on the wall, the LEDs show you right where the stud is. HART stud finders are the most accurate stud finders because they have more sensors. Other stud finders typically have only 1 or 2 sensors. The HART Professional has 9 so you can find stud positions with unbeatable accuracy. The display allows you to see the full width of objects such as single studs, wires and pipes. When a live electrical wire is detected, the yellow lightning bolt symbol may illuminate to indicate the presence of live wires. The assembled product weighs 5.3oz.