Voltage detectors have visual, audible, or vibration indicators that signal the presence of voltage in test objects without making direct contact with them. Voltage testers contact test objects and visually or audibly indicate the presence or absence of an electrical charge. Continuity testers are handheld units that contact test objects for voltage and continuity testing. These instruments help electricians, contractors, technicians, and operators safely troubleshoot and service faulty wiring and equipment such as circuit breakers, switches, outlets, cables, wires, and other conductors in homes, industrial facilities, or remote locations.