Stanley 0-77-110 Intellisensor Stud Sensor 100 The Stanley 0-77-110 Stud Sensor locates the edges of studs or joists through drywall and other common wallboards. It has a Maximum depth of 19 mm, a +/-3 mm wood stud centre detection accuracy and a +/-6 mm metal stud centre detection accuracy. The Sensor works off a 9V battery and features automatic shut off. The body has a pencil notch for marking and an LED display and buzzer indicates stud and joist edges. Continuous live wire detection. The battery is not included. Features: Stud sensor locates the edges of studs or joists through drywall and other common wallboards. Maximum depth 19mm Automatic shut off Pencil notch for marking LED display and buzzer indicates stud and joist edges Specification: Maximum depth 19 mm +/-3 mm wood stud centre detection accuracy +/-6 mm metal stud centre detection accuracy